Methods for electrochemiluminescence detection

Abstract

The present disclosure relates to novel compositions comprising electrochemiluminescence (ECL) coreactants. In embodiments, the compositions further comprise an ionic component, a surfactant, or a combination thereof. In embodiments, the ECL coreactant is triethanolamine (TEA), tert-butyldiethanolamine (tBDEA), methyldibutylethanolamine (MDEA), 3-[bis-(2-hydroxy-ethyl)-amino]-propane-1-sulfonic acid (DEA-PS), or a combination thereof. Methods of using the compositions and kits comprising the compositions are also provided herein, including methods of using ECL-labeled oligonucleotide probes with quenching moieties.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 295,470, filed December 30, 2021, which is expressly incorporated by reference in its entirety.

[0002] Reference to a sequence listing, table, or computer program listing This application has been filed with an electronic Sequence Listing, which is provided as a file named MSD_002WO2_Sequence_Listing.xml (last saved on December 22, 2022, size: 8.61 kb). The information contained therein is incorporated herein by reference in its entirety. [Background technology]

[0003] Several commercially available instruments use electrochemiluminescence (ECL) for analytical measurements. Compounds that interact with ECL labels to produce ECL are called ECL coreactants. Commonly used coreactants include Ru(Bpy)3 +2Examples of ECL-active compounds include tertiary amines for ECL derived from chromosomes (see, e.g., US 5,846,485), oxalates, and persulfates, and hydrogen peroxide for luminol-derived ECL (see, e.g., US 5,240,863). The light generated by an ECL label can be used as a reporter signal in diagnostic procedures (see, e.g., US 5,238,808). For example, an ECL label can be covalently attached to a detection reagent, and the participation of the detection reagent in the binding interaction can be monitored by measuring the ECL released from the ECL label. Alternatively, the ECL signal from an ECL-active compound can indicate the chemical environment (see, e.g., US 5,641,623, which describes an ECL assay that monitors the formation or destruction of an ECL coreactant). ECL-based assays are disclosed in U.S. Patent Nos. 5,093,268, 5,147,806, 5,324,457, 5,591,581, 5,597,910, 5,641,623, 5,643,713, 5,679,519, 5,705,402, 5,846,485, 5,866,434, 5,786,141, 5,731,147, 6,066,448, 6,136,268, 5,77 Nos. 6,672, 5,308,754, 5,240,863, 6,207,369, 5,589,136, and 6,919,173, and WO 99 / 63347, WO 00 / 03233, WO 99 / 58962, WO 99 / 32662, WO 99 / 14599, WO 98 / 12539, WO 97 / 36931, and WO 98 / 57154, each of which is incorporated herein by reference in its entirety.

[0004] Commercially available ECL instruments have become widely used due to their sensitivity, dynamic range, accuracy, and especially their tolerance for complex sample matrices. Several types of commercial instrumentation are available for performing ECL-based measurements (see, for example, Debad, JD, et al., 2004. Clinical and Biological Applications of ECL, in: Electrogenerated Chemiluminescence. Marcel Dekker, pp. 43-78). ECL devices are further described in, for example, U.S. Pat. Nos. 5,935,779 and 5,993,740 (bead-based ECL assays), U.S. Pat. Nos. 6,140,045, 6,066,448, 6,090,545, 6,207,369, and WO 98 / 12539 (ECL assays using immobilized binding reagents), U.S. Pat. Nos. 6,977,722 and 7,842,246 (multiwell plates with integrated electrodes for ECL assays), and U.S. Publication Nos. 2012 / 0190589 and US2012 / 0178091 (cartridge-based ECL assays), each of which is incorporated herein by reference in its entirety.

[0005] The ECL coreactant tripropylamine (TPA) is typically used in ECL-based assays. Molecular beacons are oligonucleotide molecular probes that contain a stem and loop, a quenching moiety, and a fluorescent moiety, which interact to reduce the fluorescent signal from the fluorescent moiety when the quenching moiety is in close proximity to the fluorescent moiety in the absence of a target sequence. Under ideal conditions, this molecular probe can increase fluorescence by 200-fold upon hybridization. However, this type of molecular beacon is typically limited to assaying a single analyte (or, in the above case, the target sequence) at a given time. Furthermore, such molecular beacons with fluorescent moieties are not easily controlled and have a limited lifetime due to photobleaching. In addition, these types of molecular beacons require multiple incubation and washing cycles, which can increase the duration of the assay and therefore reduce its efficiency. Examples of molecular beacon probes with ECL labels are disclosed in Chem. Commun. 21:2710-2711 (2003) and Sensors & Actuators: B. Chemical 330:129261 (2021). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 5,846,485 [Patent Document 2] U.S. Patent No. 5,240,863 [Patent Document 3] U.S. Patent No. 5,238,808 [Patent Document 4] U.S. Patent No. 5,641,623 [Patent Document 5] U.S. Patent No. 5,093,268 [Patent Document 6] U.S. Patent No. 5,147,806 [Patent Document 7] U.S. Patent No. 5,324,457 [Patent Document 8] U.S. Patent No. 5,591,581 [Patent Document 9] U.S. Patent No. 5,597,910 [Patent Document 10] U.S. Patent No. 5,641,623 [Patent Document 11] U.S. Patent No. 5,643,713 [Patent Document 12] U.S. Patent No. 5,679,519 [Patent Document 13] U.S. Patent No. 5,705,402 [Patent Document 14] U.S. Patent No. 5,846,485 [Patent Document 15] U.S. Patent No. 5,866,434 [Patent Document 16] U.S. Patent No. 5,786,141 [Patent Document 17] U.S. Patent No. 5,731,147 [Patent Document 18] U.S. Patent No. 6,066,448 [Patent Document 19] U.S. Patent No. 6,136,268 [Patent Document 20] U.S. Patent No. 5,776,672 [Patent Document 21] U.S. Patent No. 5,308,754 [Patent Document 22] U.S. Patent No. 5,240,863 [Patent Document 23] U.S. Patent No. 6,207,369 [Patent Document 24] U.S. Patent No. 5,589,136 [Patent Document 25] U.S. Patent No. 6,919,173 [Patent Document 26] International Publication No. 1999 / 63347 [Patent Document 27] International Publication No. 2000 / 03233 [Patent Document 28] International Publication No. 1999 / 58962 [Patent Document 29] International Publication No. 1999 / 32662 [Patent Document 30] International Publication No. 1999 / 14599 [Patent Document 31] International Publication No. 1998 / 12539 [Patent Document 32] International Publication No. 1997 / 36931 [Patent Document 33] International Publication No. 1998 / 57154 [Patent Document 34] U.S. Patent No. 5,935,779 [Patent Document 35] U.S. Patent No. 5,993,740 [Patent Document 36] U.S. Patent No. 6,140,045 [Patent Document 37] U.S. Patent No. 6,090,545 [Patent Document 38] International Publication No. 1998 / 12539 [Patent Document 39] U.S. Patent No. 6,977,722 [Patent Document 40] U.S. Patent No. 7,842,246 [Patent Document 41] US Patent Application Publication No. 2012 / 0190589 [Patent Document 42] US Patent Application Publication No. 2012 / 0178091 Summary of the Invention [Means for solving the problem]

[0007] An embodiment of the present disclosure is an electrochemiluminescence (ECL) detection method comprising: a) providing a substrate comprising an electrode having a binding reagent immobilized on a surface of the substrate; b) contacting the substrate with a composition, the composition comprising: i) a binding partner and / or binding complex comprising an oligonucleotide, wherein a binding reagent binds the binding partner and / or binding complex; ii) a plurality of ECL-labeled oligonucleotide probes comprising oligonucleotide sequences complementary to the oligonucleotide sequences of the binding partners and / or oligonucleotides of the binding complex; iii) contacting with an ECL coreactant that is not TPA; c) hybridizing a portion of the plurality of ECL-labeled oligonucleotide probes to oligonucleotides of the binding partners and / or binding complexes, wherein the binding partners and / or binding complexes are bound by a binding reagent, and another portion of the plurality of ECL-labeled oligonucleotide probes is not hybridized to the oligonucleotides of the binding partners and / or binding complexes bound by the binding reagent; d) selectively dequenching a portion of the plurality of ECL-labeled probes hybridized to the binding partner and / or oligonucleotide of the binding complex; and e) applying a voltage to the electrodes to generate ECL; f) measuring ECL, wherein a portion of the plurality of ECL-labeled oligonucleotide probes that are not hybridized to oligonucleotides of the binding partner and / or binding complex are not removed from the composition prior to applying a voltage and measuring the ECL. In embodiments, b) contacting the substrate with the composition comprises: b') contacting the substrate with a composition comprising a binding partner and / or binding complex; b'') contacting the substrate with a composition comprising a plurality of ECL-labeled oligonucleotide probes; b''') contacting the substrate with a composition comprising an ECL coreactant. In an embodiment, each of steps b'), b'') and b''') is performed sequentially. In an embodiment, at least two of steps b'), b'') and b''') are performed simultaneously. In an embodiment, the method comprises: b') contacting the substrate with a first composition comprising a binding partner and / or binding complex, and immobilizing the binding partner and / or binding complex on the surface by binding to the binding reagent; b'') contacting the substrate containing the immobilized binding partners and / or binding complexes with a second composition comprising a plurality of ECL-labeled oligonucleotide probes and an ECL coreactant; or b') contacting the substrate with a first composition comprising a binding partner and / or binding complex and a plurality of ECL-labeled oligonucleotide probes, wherein a portion of the plurality of ECL-labeled oligonucleotide probes hybridize to the oligonucleotides of the binding partner and / or binding complex, and immobilizing the binding partner and / or binding complex on the surface by binding to a binding reagent; b'') contacting the substrate containing the immobilized binding partner and / or binding complex with a second composition containing an ECL coreactant; or b') contacting the substrate with a first composition comprising a binding partner and / or binding complex, and immobilizing the binding partner and / or binding complex on the surface by binding to the binding reagent; b'') contacting the substrate comprising the immobilized binding partners and / or binding complexes with a second composition comprising a plurality of ECL-labeled oligonucleotide probes, allowing a portion of the plurality of ECL-labeled oligonucleotide probes to hybridize to the oligonucleotides of the immobilized binding partners and / or binding complexes; b''') contacting the substrate with a third composition comprising an ECL coreactant. In embodiments, the method further comprises washing the substrate after contacting the substrate with the binding partners and / or binding complexes to remove binding partners and / or binding complexes that are not bound by the binding reagent, the washing being prior to contacting the substrate with a composition comprising a plurality of ECL-labeled oligonucleotide probes.

[0008] An embodiment of the present disclosure is an electrochemiluminescence (ECL) detection method comprising: a) providing a substrate comprising an electrode, the substrate having a binding partner and / or binding complex comprising an oligonucleotide immobilized on a surface of the substrate; b) contacting the substrate with a composition, the composition comprising: i) a plurality of ECL-labeled oligonucleotide probes comprising oligonucleotide sequences complementary to the oligonucleotide sequences of the binding partners and / or oligonucleotides of the binding complex; ii) contacting with an ECL coreactant that is not TPA; c) hybridizing a portion of the plurality of ECL-labeled oligonucleotide probes to the oligonucleotides of the immobilized binding partner and / or binding complex, wherein another portion of the plurality of ECL-labeled oligonucleotide probes is not hybridized to the oligonucleotides of the immobilized binding partner and / or binding complex; d) selectively dequenching a portion of the plurality of ECL-labeled probes hybridized to the binding partner and / or oligonucleotide of the binding complex; and e) applying a voltage to the electrodes to generate ECL; f) measuring ECL, wherein a portion of the plurality of ECL-labeled oligonucleotide probes that are not hybridized to oligonucleotides of the binding partner and / or binding complex are not removed from the composition prior to applying a voltage and measuring the ECL. In embodiments, b) contacting the substrate with the composition comprises: b') contacting the substrate with a composition comprising a plurality of ECL-labeled oligonucleotide probes; b'') contacting the substrate with a composition comprising an ECL coreactant. In embodiments, each of steps b') and b'') is performed sequentially. In embodiments, each of steps b') and b'') is performed simultaneously, and optionally, the multiple ECL-labeled oligonucleotide probes and ECL co-reactants are in a single composition.

[0009] Embodiments of the present disclosure, including those in the preceding paragraphs, include embodiments in which the binding partner and / or binding complex comprises an analyte. In embodiments, the analyte comprises a peptide. In embodiments, the analyte comprises an oligonucleotide. In embodiments, the analyte is an oligonucleotide of the binding partner and / or binding complex. In embodiments, the analyte is labeled with an oligonucleotide. In embodiments, the analyte is labeled with an oligonucleotide by combining the analyte with a detection reagent comprising the oligonucleotide. In embodiments, the oligonucleotide of the binding partner and / or binding complex comprises multiple copies of a sequence complementary to the oligonucleotide sequences of the plurality of ECL-labeled oligonucleotide probes. In embodiments, prior to contacting the substrate with the plurality of ECL-labeled oligonucleotide probes, an amplification reaction is performed to generate multiple copies of a sequence complementary to the oligonucleotide sequences of the plurality of ECL-labeled oligonucleotide probes. In embodiments, the analyte is labeled with an oligonucleotide by combining the analyte with a detection reagent comprising an oligonucleotide primer, and the oligonucleotide primer is extended by a polymerase to generate oligonucleotides comprising multiple copies of a sequence complementary to the oligonucleotide sequences of the ECL-labeled oligonucleotide probes. In embodiments, the amplification reaction or primer extension is a rolling circle amplification reaction. In embodiments, the ECL-labeled oligonucleotide probe comprises a stem-loop or hairpin structure, an ECL label, and a quenching moiety, wherein the quenching moiety is adjacent to and quenches the ECL label when the oligonucleotide probe is in the stem-loop or hairpin configuration, but does not quench the ECL label when the stem-loop or hairpin structure is in an open configuration, and selective dequenching comprises hybridizing a portion of the ECL-labeled oligonucleotide probe to the binding partner and / or oligonucleotide of the binding complex in the open configuration. In embodiments, the ECL-labeled oligonucleotide probe comprises an ECL label and a quenching moiety, wherein the quenching moiety is adjacent to and quenches the ECL label when the oligonucleotide probe is in a linear confirmation, and selective dequenching comprises hybridizing a portion of the ECL-labeled oligonucleotide probe to the binding partner and / or oligonucleotide of the binding complex in the open configuration.The method includes selectively cleaving the quenching site from only the portion of the plurality of ECL-labeled probes hybridized to the oligonucleotides of the binding partner and / or binding complex, such that the quenching site is released into solution and is no longer in proximity to the ECL labels of the hybridized ECL-labeled probes that remain hybridized to the oligonucleotides of the binding partner and / or binding complex after cleavage of the quenching site. In embodiments, the cleavage is performed by an enzyme. In embodiments, the enzyme is selected from the group consisting of a nicking restriction endonuclease, RNase H2, and a polymerase with 5' exonuclease activity. In embodiments, the enzyme cleaves only the ECL-labeled oligonucleotide probes, leaving the oligonucleotides of the binding partner and / or binding complex intact. In embodiments, the enzyme is a nicking restriction endonuclease that recognizes a sequence within the hybridized ECL-labeled probe, or RNase H2 that recognizes an RNA base within the hybridized ECL-labeled probe. In embodiments, the enzyme is a polymerase with 5' exonuclease activity, and the method further comprises hybridizing a primer to the oligonucleotide of the binding partner and / or binding complex at the 5' position of the hybridized ECL-labeled probe, and allowing the polymerase with 5' exonuclease activity to extend the primer to the hybridized ECL-labeled probe, wherein the 5' exonuclease activity cleaves the quenched site of the hybridized ECL-labeled probe, and the ECL-labeled probe comprises a portion that is resistant to 5' exonuclease activity. In embodiments, the ECL coreactant is 3-(di-n-propylamino)-propanesulfonic acid, 4-(di-n-propylamino)-butanesulfonic acid, 4-[bis-(2-hydroxyethane)-amino]-butanesulfonic acid, piperidine-N-(3-propanesulfonic acid), azepane-N-(3-propanesulfonic acid), piperidine-N-(3-propionic acid) (PPA), 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO), 3-morpholinepropanesulfonic acid (MOPS), N-(2-hydroxyethyl)piperazine-N′-3-propanesulfonic acid (EPPS),N-(2-hydroxyethyl)piperazine-N'-3-ethanesulfonic acid (BES), piperazine-N,N'-bis(2-ethanesulfonic acid) (PIPES), triethanolamine (TEA), N-2-hydroxypiperazine-N-2-ethanesulfonic acid (HEPES), piperazine-N,N'-bis-4-butanesulfonic acid, homopiperidine-N-3-propanesulfonic acid, piperazine-N,N'-bis-3- Propanesulfonic acid, piperidine-N-3-propanesulfonic acid, piperazine-N-2-hydroxyethane-N'-3-methylpropanoate, piperazine-N,N'-bis-3-methylpropanoate, 1,6-diaminohexane-N,N,N',N'-tetraacetic acid, N,N-bispropyl-N-4-aminobutanesulfonic acid, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid (TES), 1, The hydroxypropyl methylamino compound is selected from the group consisting of 3-bis[tris(hydroxymethyl)methylamino]propane (bis-trispropane), 3-dimethylamino-1-propanol, 3-dimethylamino-2-propanol, N,N,N',N'-tetrapropylpropane-1,3-diamine (TPA dimer), piperazine-N,N'-bis(2-hydroxypropane)sulfonic acid (POPSO) and 2-hydroxy-3-[4-(2-hydroxyethyl)piperazin-1-yl]propane-1-sulfonic acid (HEPPSO), N-butyldiethanolamine (BDEA), 2-dibutylaminoethanol (DBAE), tert-butyldiethanolamine (tBDEA), methyldiethanolamine (MDEA), 3-[bis-(2-hydroxyethyl)amino]propane-1-sulfonic acid (DEA-PS), and combinations thereof. In embodiments, the ECL coreactant is TEA or is selected from the group consisting of TEA, tBDEA, BDEA, MDEA, DEA-PS, and combinations thereof, or TEA, tBDEA, MDEA, DEA-PS, and combinations thereof. In embodiments, the quenching moiety is selected from the group consisting of ATTO 540Q, ATTO 575Q, ATTO 580Q, ATTO 612Q, Iowa Black FQ, Iowa Back RQ, QSY 21,The ECL label is selected from the group consisting of IRDye QC-1, BHQ0, BHQ1, BHQ-2, BHQ-3, dabcyl, QSY 7, QSY 9, QSY 21, QSY 35, QXL 490, QXL 520, QXL 570, QXL 670, ferrocene, iron bipyridine, and combinations thereof. In embodiments, the ECL label is an organometallic complex containing ruthenium, osmium, iridium, rhenium, and / or a lanthanide metal. The ECL label comprises tris(bipyridine)ruthenium or modified tris(bipyridine)ruthenium. The ECL label is represented by Formula II: [ka] (II). In embodiments, the co-reactant is in the composition of any one of the embodiments above and herein. In embodiments, the co-reactant is in the composition of any one of numbered items 1-69. In embodiments, the co-reactant includes TEA.

[0010] The following drawings form part of the present specification and are included to further demonstrate illustrative embodiments of certain aspects of the present disclosure. [Brief explanation of the drawings]

[0011] [Figure 1A] Figures 1A and 1B relate to Example 1 and show the results of one embodiment of an ECL-based assay. A panel of ECL coreactants in combination with one of two surfactants was tested for ECL generation and the ability to distinguish between surface-bound ("BTI") and free (in solution, "FT") ECL labels in a solid surface ECL assay. Figure 1A shows the ECL signal measured at BTI, FT, and background signal ("D100") using ECL read buffer only (no label). Figure 1B shows the ratio of ECL signal from bound label to ECL signal from free label ("BTI / FT") and the signal-to-background ratio ("S / B"). [Figure 1B] Same as above. [Figure 2A]Figures 2A-2C relate to Example 2 and show results of one embodiment of an ECL-based assay. Figure 2A shows plots of ECL generated from BTI and FT with different concentrations of TEA and the BTI / FT ratio. Figure 2B shows the measured ECL signal from BTI, FT, and background (D100) with different concentrations of TEA. Figure 2C shows the BTI / FT ratio, S / B ratio, and percent ECL generation compared to PIPES ECL read buffer. [Figure 2B] Same as above. [Figure 2C] Same as above. [Figure 3A] Figures 3A and 3B relate to Example 3 and show the results of one embodiment of an ECL-based assay. Figure 3A shows the change in ECL signal as a function of PIPES concentration. Figure 3B shows the change in ECL signal as a function of PIPES or TEA concentration. [Figure 3B] Same as above. [Figure 4A]

[0033] Figure 4A shows an embodiment of an ECL-based assay described herein and further described in Example 4. Figure 4A shows a "standard" two-step wash assay in which capture antibodies ("cAb", binding reagents) immobilized on a surface are contacted with a mixture of analytes (one of which is specifically bound to the capture antibody), and then the surface is washed, resulting in capture of the analyte on the surface. A mixture of detection antibodies ("dAb", detection reagents), each containing an ECL label and one of which specifically binds to the analyte, is then added to the surface, and the surface is then washed, resulting in a binding complex comprising the cAb, the analyte, and the dAb. An ECL read buffer is then added to the surface, and the generated ECL is read by an ECL reading instrument. [Figure 4B]

[0033] Figure 4B shows an embodiment of an ECL-based assay described herein and further described in Example 4. Figure 4B shows a "one-step" assay in which a capture antibody on a surface is contacted with an analyte mixture, and then the surface is washed as in Figure 4A. A detection antibody mixture is then added, followed by an ECL read buffer, with no washes between the addition of the detection antibody mixture and the ECL read buffer. The ECL generated is then read by an ECL reading instrument. [Figure 4C]

[0033] Figure 4C shows an embodiment of an ECL-based assay described herein and further described in Example 4. Figure 4C shows a "one-step, no-wash" assay in which the capture antibody on the surface is contacted with an analyte mixture and a detection antibody mixture, followed by an ECL read buffer, with no washes between any of the steps. The ECL generated is then read by an ECL reading instrument. [Figure 4D] An embodiment of an ECL-based assay described herein and further described in Example 4 is shown. Figure 4D shows a "mock ECL-labeled" assay in which a capture antibody on a surface is contacted with an analyte mixture, the surface is washed, a detection antibody mixture is added, and the surface is washed again as needed, resulting in a binding complex as shown in Figure 4A. An ECL read buffer is then added to the surface along with a detection antibody that contains an ECL label and does not bind to any component of the binding complex on the surface, which serves as a proxy for the "free" ECL label in solution. The generated ECL is then read by an ECL reading instrument. [Figure 4E]

[0033] Figure 4E shows an embodiment of an ECL-based assay described herein and further described in Example 4. Figure 4E shows a multiplexed version of a "standard" two-step washing assay in which one or more surfaces contain multiple binding domains, each containing a capture antibody capable of binding to an analyte in an analyte mixture. The surface(s) containing the binding domains are washed after the addition of the analyte mixture, resulting in the capture of multiple analytes on the binding domains. A mixture of detection antibodies, each containing an ECL label and capable of binding to an analyte in the analyte mixture, is then added to the surface(s), and the surface is then washed, resulting in multiple binding complexes, each containing a cAb, an analyte, and a dAb. An ECL read buffer is then added to the surface, and the generated ECL is read by an ECL instrument. [Figure 4F]

[0033] Figure 4F shows an embodiment of an ECL-based assay described herein and further described in Example 4. Figure 4F shows a multiplexed version of a "single-step" assay in which one or more surfaces contain multiple binding domains, each containing a capture antibody capable of binding to an analyte in an analyte mixture. The surface(s) containing the binding domains are washed after the addition of the analyte mixture, as in Figure 4E. A detection antibody mixture is added to form multiple binding complexes, and then an ECL read buffer is added, with no washes between the addition of the detection antibody mixture and the ECL read buffer. The generated ECL is then read by an ECL reading instrument. [Figure 4G]

[0033] Figure 4G shows an embodiment of an ECL-based assay described herein and further described in Example 4. Figure 4G shows a multiplexed version of a "one-step, no-wash" assay in which one or more surfaces contain multiple binding domains, each containing a capture antibody capable of binding to an analyte in an analyte mixture. The surface(s) containing the binding domains are contacted with the analyte mixture and the detection antibody mixture to form multiple binding complexes, and then an ECL read buffer is added, with no washing between any steps. The generated ECL is then read by an ECL reading instrument. [Figure 4H]An embodiment of an ECL-based assay described herein and further described in Example 4 is shown. Figure 4H shows a multiplexed version of a "mock ECL-labeled" assay in which one or more surfaces contain multiple binding domains, each containing a capture antibody capable of binding to an analyte in the analyte mixture. The surface(s) containing the binding reagents are contacted with the analyte mixture, the surface is washed, a detection antibody mixture is added, and the surface is washed again as needed, resulting in multiple binding complexes, as shown in Figure 4E. An ECL read buffer is then added to the surface along with a detection antibody that contains an ECL label and does not bind to any component of the binding complex on the surface, serving as a proxy for the "free" ECL label in solution. The generated ECL is then read by an ECL reading instrument. [Figure 5A] Referring to Example 5A, results of one embodiment of an ECL-based assay are shown. Figure 5A shows the specific ECL signal and nonspecific binding (NSB) results from three different multiplexed assay formats (shown in Figures 4E, 4F, and 4H) using BDEA, PIPES, and TEA read buffers. [Figure 5B] Figure 5B shows the results of one embodiment of an ECL-based assay, related to Example 5A. Figure 5B shows the lower limit of detection (LLOD) of the assay in Figure 5A. [Figure 5C] Figure 5C shows the results of one embodiment of an ECL-based assay, related to Example 5A. Figure 5C shows a relative comparison of the ECL and NSB results from Figure 5A. [Figure 5D]

[0049] Figure 5D shows the results of one embodiment of an ECL-based assay, related to Example 5A. Figure 5D shows a comparison of signal-to-background (S / B) and signal-to-noise (S / N) ratios across all ECL read buffers and assay formats. [Figure 6A] Related to Example 5B, results of one embodiment of an ECL-based assay are shown in Figure 6A. Specific ECL signal and nonspecific binding (NSB) results from three different multiplexed assay formats (shown in Figures 4E, 4F, and 4G) using BDEA, PIPES, and TEA read buffers. [Figure 6B]

[0033] Figure 6B shows the results of one embodiment of an ECL-based assay, related to Example 5B. Figure 6B shows the lower limit of detection (LLOD) of the assay in Figure 6A. [Figure 6C]

[0033] Figure 6C shows the results of one embodiment of an ECL-based assay, related to Example 5B. Figure 6C shows a relative comparison of the ECL and NSB results from Figure 6A. [Figure 7A]

[0049] Figure 7A shows a list of sample matrices tested in a one-step, no-wash ECL assay using a TEA read buffer. Figure 7B shows a list of interferents added to the sample matrix of Figure 7A, tested in a one-step, no-wash ECL assay using a TEA read buffer. [Figure 7B] Same as above. [Figure 8A] Related to Example 6, results of one embodiment of an ECL-based assay are shown. Figure 8A shows the results of ECL signals generated from TEA read buffer containing bound ECL label ("Bound") and free ECL label ("Free") using different sample matrices mixed with diluent. "HO" indicates the signal from a control in which water was used instead of sample matrix before the TEA read buffer. Column headers containing "Free" indicate 6 nM free ECL label in diluent. Figure 8B shows the results of Figure 8A normalized to the ECL signal generated from an assay in which no sample matrix was added. [Figure 8B] Same as above. [Figure 9A]

[0049] Figure 9A shows the results of one embodiment of an ECL-based assay, related to Example 6. Figure 9A shows the results of ECL signals generated from TEA read buffer containing bound and free ECL label with different interfering substances in different sample matrices. Figure 9B shows the results of Figure 9A normalized to the ECL signal generated from an assay without added sample matrix and interfering substances. [Figure 9B] Same as above. [Figure 10A]

[0049] Figure 10A shows the results of one embodiment of an ECL-based assay, related to Example 6. Figure 10A shows the results of ECL signals generated from TEA read buffer containing free ECL label ("D3+STAG") in different sample matrices. Column headers containing "Free" indicate 240 nM free ECL label in diluent. Figure 10B shows the results of Figure 10A normalized to the ECL signal generated from an assay in which no sample matrix was added. [Figure 10B] Same as above. [Figure 11A]

[0049] Figure 11A shows the results of one embodiment of an ECL-based assay, related to Example 6. Figure 11A shows the results of the ECL signal generated from a TEA read buffer containing 240 nM free ECL with different interferents in different sample matrices. Figure 11B shows the results of Figure 11A normalized to the ECL signal generated from an assay without added sample matrix and interferents. [Figure 11B] Same as above. [Figure 12]

[0049] Figure 12 relates to Example 7 and shows the results of one embodiment of an ECL-based assay. The combinations of ECL coreactants described in Example 1 were tested in an ECL-based assay. The top right side of the chart in Figure 12 shows the ECL signal generated from the BTI, and the bottom left side of the chart in Figure 12 shows the ratio of the ECL signal of the mixed ECL coreactants to the sum of the signals generated by the individual ECL coreactants. [Figure 13A] Results of one embodiment of an ECL-based assay are shown in connection with Example 8. The ECL coreactants described in Example 1 were tested for sensitivity to the presence of TRITON® X-100. Figure 13A shows the ECL signals from BTI and FT for each ECL reactant in TRITON™ X-100 (TX100) and PEG(18) tridecyl ether (PEG18TDE). [Figure 13B]

[0071] Referring to Example 8, the results of one embodiment of an ECL-based assay are shown. The ECL coreactant described in Example 1 was tested for sensitivity to the presence of TRITON™ X-100. Figure 13B shows the ratio of ECL generated in TRITON™ X-100 to PEG(18) tridecyl ether. [Figure 14] FIG. 1 is a diagram of one embodiment of a method for detecting target oligonucleotide analyte(s) utilizing ECL-labeled molecular beacon oligonucleotide probes and co-reactants (co-reactants not shown). [Figure 15] FIG. 1 is a diagram of one embodiment of a method for detecting target oligonucleotide analyte(s) utilizing ECL-labeled molecular beacon oligonucleotide probes and a TEA coreactant (coreactant not shown), as described in Examples 10-12. [Figure 16] FIG. 1 is a diagram of an embodiment of an ECL-labeled molecular beacon probe prepared in Example 9 and used in the experiments described in Examples 10-12. [Figure 17A] 17A and 17B are graphical representations of the results of one embodiment of the no-wash experiment described in Example 10 using the ECL-labeled molecular beacon probes of Example 9. Figure 17A shows the ECL signal for increasing concentrations of target oligonucleotide free in solution using a read buffer containing TPA. [Figure 17B] Figure 17B is a graphical representation of the results of one embodiment of the no-wash experiment described in Example 10 using the ECL-labeled molecular beacon probes of Example 9. Figure 17B shows the ECL signal for increasing concentrations of target oligonucleotides immobilized on the surface of a substrate using a read buffer containing TPA. [Figure 17C] Figure 17C is a graphical representation of the results of one embodiment of the no-wash experiment described in Example 10 using the ECL-labeled molecular beacon probe of Example 9. Figure 17C shows the ECL signal for increasing concentrations of target oligonucleotide free in solution using a read buffer containing TEA. [Figure 17D]Figure 17D is a graphical representation of the results of one embodiment of the no-wash experiment described in Example 10 using the ECL-labeled molecular beacon probes of Example 9. Figure 17D shows the ECL signal for increasing concentrations of target oligonucleotides immobilized on the surface of a substrate using a read buffer containing TEA. [Figure 18A] We report the results of the no-wash broad concentration range experiment described in Example 11 using the ECL-labeled molecular beacon probes of Example 9. Figure 18A shows the ECL signal for increasing concentrations of target oligonucleotides immobilized on the surface of a substrate using a read buffer containing TEA. [Figure 18B] We report the results of the no-wash broad concentration range experiment described in Example 11 using the ECL-labeled molecular beacon probes of Example 9. Figure 18B is a chart listing the ECL signal intensities shown in Figure 18A for each MB probe with decreasing concentrations of target oligonucleotide. [Figure 19A] We report the results of one embodiment of the two-step no-wash experiment described in Example 12, using the ECL-labeled molecular beacon probes of Example 9. Figure 19A shows the ECL signal with increasing concentrations of target oligonucleotides immobilized on the surface of a substrate, using a read buffer containing TEA. [Figure 19B] We report the results of one embodiment of the two-step no-wash experiment described in Example 12, using the ECL-labeled molecular beacon probes of Example 9. Figure 19B is a chart listing the ECL signal intensities shown in Figure 18A for each MB probe with decreasing concentrations of target oligonucleotide. [Figure 20]

[0023] Figure 1 is a diagram of one embodiment of a method for detecting a peptide analyte indirectly labeled with an oligonucleotide primer, which utilizes an ECL-labeled molecular beacon oligonucleotide probe that binds to an extended sequence derived from the primer. No wash step is performed after addition of the ECL-labeled oligonucleotide probe. In this embodiment, streptavidin is the binding reagent, and the biotinylated capture antibody, the peptide analyte, and the second antibody comprising the extended oligonucleotide primer together form a binding complex. [Figure 21] FIG. 1 is a diagram of one embodiment of a method for detecting a target oligonucleotide analyte(s) utilizing an ECL-labeled oligonucleotide probe, in which a quenching moiety is selectively cleaved from the hybridized probe by an enzyme, e.g., a nicking endonuclease, dequenching the ECL label of the probe while leaving the remainder of the ECL-labeled probe hybridized to the target oligonucleotide. DETAILED DESCRIPTION OF THE INVENTION

[0012] The disclosed ECL coreactants provide consistent ECL generation across different assay formats. For example, compositions herein containing triethanolamine (TEA) have been found to be useful in ECL-based assays that do not require a wash step. Many ECL-based assays performed on solid surfaces include at least one wash step to remove unbound ECL label before detecting the ECL label on the surface (i.e., a "wash" assay). A wash step may be eliminated if the detection method can effectively distinguish between ECL label bound to the surface (e.g., as part of a binding complex to be detected) and unbound "free" ECL label in solution. "No-wash" assay formats, in which a wash step is eliminated, are often advantageous because wash steps can be difficult or cumbersome to perform in many situations. However, no-wash assay formats are typically difficult to develop due to high background ECL signal resulting from incomplete discrimination between free and bound ECL label present in the reaction mixture.

[0013] In ECL-based assays performed on solid surfaces, triethanolamine (TEA) has surprisingly been discovered to highly discriminate between unbound ("free") ECL labels in solution and surface-bound ECL labels. The compositions described herein, including TEA, increase the ratio of ECL signal from bound to free labels compared to conventional compositions containing conventional coreactants such as tripropylamine (TPA). Thus, the compositions described herein provide improved assay performance, particularly when measuring low-affinity interactions, which require the presence of high concentrations of ECL labels in the reaction but are also expected to suffer significant signal loss due to dissociation of the binding complex during washing steps.

[0014] For example, ECL signals generated from compositions herein containing TEA, tert-butyldiethanolamine (tBDEA), methyldiethanolamine (MDEA), and / or 3-[bis-(2-hydroxyethyl)-amino]propane-1-sulfonic acid (DEA-PS) offer additional benefits, such as improved consistency of performance between different compositions based on the presence or absence of surfactants or the identity of the surfactant. Notably, compositions perform similarly whether they contain no surfactant, a mild surfactant that does not disrupt lipid bilayer membranes (e.g., polyethylene glycol (18) tridecyl ether), or a more stringent surfactant (e.g., TRITON™ X-100). Thus, harsh surfactants (e.g., TRITON™ X-100, which disrupt lipid bilayer membranes that are part of specific analytes of interest, such as whole cells or extracellular vesicles) are not required for compositions containing ECL coreactants described herein, in contrast to tripropylamine (TPA), a typical ECL coreactant that typically requires TRITON™ X-100 for optimal ECL generation. Thus, the compositions herein are useful in assays for detecting analytes that are sensitive to harsh detergents. Furthermore, the ECL signal of the ECL coreactants is not significantly affected by the presence of different detergents, and therefore these ECL coreactants are versatile and can be easily incorporated into different formulations while maintaining their ECL-generating capabilities.

[0015] Thus, compositions herein that include, for example, TEA, tBDEA, MDEA, and / or DEA-PS advantageously expand the variety of ECL-based assays that can be performed.

[0016] Unless otherwise defined herein, scientific and technical terms used in this disclosure shall have the meanings commonly understood by those of ordinary skill in the art. Further, unless otherwise required by context, singular terms shall include the plural and plural terms shall include the singular. The articles "a" and "an" are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, "an element" means one element or more than one element.

[0017] Use of the term "or" in the claims is used to mean "and / or" unless expressly indicated to refer only to alternatives, or alternatives are mutually exclusive, but the present disclosure supports a definition that refers only to alternatives and "and / or."

[0018] As used herein, the terms "comprising" (and any variation or form of "comprising," such as "comprise" and "comprises"), "having" (and any variation or form of "having," such as "have" and "has"), "including" (and any variation or form of "including," such as "includes" and "include"), or "containing" (and any variation or form of "containing," such as "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0019] The use of the term "for example" and its corresponding abbreviation "eg" (whether italicized or not) means that the particular terms described are representative examples and embodiments of the present disclosure that are not intended to be limited to the particular examples referenced or cited, unless expressly stated otherwise.

[0020] As used herein, "between" refers to a range that includes both endpoints. For example, a number between x and y explicitly includes the numbers x and y, and any number (including fractions and integers) contained within x and y. Furthermore, reference herein to a range of "5 to 10" includes the integers 5, 6, 7, 8, 9, and 10, as well as fractions such as 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, etc. Reference to any numerical range explicitly includes each number (including fractions and integers) encompassed by that range. By way of example, a range of "at least 50" or "at least about 50" includes integers such as 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, etc., and fractions such as 50.1, 50.2, 50.3, 50.4, 50.5, 50.6, 50.7, 50.8, 50.9, etc. By way of further example, reference herein to a range of "less than 50" or "less than about 50" includes integers such as 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, etc., and fractions such as 49.9, 49.8, 49.7, 49.6, 49.5, 49.4, 49.3, 49.2, 49.1, 49.0, etc.

[0021] As used herein, the terms "substantially" or "substantial" are applicable when used in a negative sense to refer to the complete or nearly complete absence of an action, characteristic, property, state, structure, item, or result. For example, a "substantially" flat surface would either be completely flat or nearly flat with the same effect as being completely flat. In a further example, a composition that is "substantially free" of a particular component would not have that component in any amount, or the component would be present in the composition in an amount so low that it would have the same effect as if the component were not present.

[0022] In embodiments, the present disclosure provides a composition comprising: (a) triethanolamine (TEA); and (b) an ionic component, wherein the composition has a pH of about 7.0 to about 8.0, and the composition is substantially free of additional pH buffering components.

[0023] In embodiments, the present disclosure provides a composition comprising: (a) triethanolamine (TEA); (b) an ionic component; and (c) an ECL label component, wherein the composition has a pH of about 7.0 to about 8.0, and the composition is substantially free of additional pH buffering components.

[0024] In embodiments, the present disclosure provides a composition comprising: (a) about 1000 mM to about 6500 mM triethanolamine (TEA); and (b) about 500 mM to about 2000 mM of an ionic component, wherein the composition has a pH of about 7.0 to about 8.0.

[0025] In embodiments, the present disclosure provides a composition comprising: (a) triethanolamine (TEA); (b) an ionic component; and (c) an alkyl ether polyethylene glycol (PEG), wherein the composition has a pH of about 7.0 to about 8.0.

[0026] In embodiments, the present disclosure provides a composition comprising (a) TEA, (b) an ionic component, and (c) optionally one or both of an ECL labeling component and a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and optionally the composition is substantially free of additional pH buffering components.

[0027] In embodiments, the present disclosure provides a composition comprising: (a) an electrochemiluminescence (ECL) coreactant selected from N-tert-butyldiethanolamine (tBDEA), methyldiethanolamine (MDEA), 3-[bis-(2-hydroxy-ethyl)-amino]-propane-1-sulfonic acid (DEA-PS), and combinations thereof; (b) an ionic component; and (c) a surfactant, wherein the composition has a pH of about 7.0 to about 8.0.

[0028] In embodiments, the present disclosure provides compositions consisting of or consisting essentially of the recited components in the recited amounts. In compositions consisting essentially of the recited components, such compositions specifically exclude components that materially affect the ECL generation properties of the composition. The ECL generation properties of a composition can be determined by methods known to those skilled in the art. For example, a composition can be contacted with a known amount of ECL label on an electrode, and a voltage can be applied to the electrode, thereby generating ECL. In embodiments, "materially unaffected" ECL generation properties mean that a composition "consisting essentially of" the recited components generates about 80%, about 90%, about 95%, about 98%, about 99%, about 100%, about 101%, about 102%, about 105%, about 110%, or about 120% of the ECL as a composition "consisting of" the recited components. In embodiments, a composition consisting essentially of the recited components specifically excludes additional ECL-generating compounds, e.g., additional ECL coreactants.

[0029] In embodiments, the present disclosure provides a composition comprising (a) triethanolamine (TEA), (b) an ionic component, and (c) a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and wherein the composition is substantially free of additional pH buffering components. In embodiments, the present disclosure provides a composition comprising (a) triethanolamine (TEA), (b) an ionic component, and (c) a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and wherein the composition is substantially free of additional pH buffering components.

[0030] In embodiments, the present disclosure provides a composition consisting essentially of (a) triethanolamine (TEA), (b) an ionic component, (c) a surfactant, and (d) an ECL-labeled component, wherein the composition has a pH of about 7.0 to about 8.0, and the composition is substantially free of additional pH buffering components. In embodiments, the present disclosure provides a composition consisting essentially of (a) triethanolamine (TEA), (b) an ionic component, (c) a surfactant, and (d) an ECL-labeled component, wherein the composition has a pH of about 7.0 to about 8.0.

[0031] In an embodiment, the present disclosure provides a composition comprising (a) about 1000 mM to about 6500 mM triethanolamine (TEA), (b) about 500 mM to about 2000 mM ionic components, and (c) a surfactant, wherein the composition has a pH of about 7.0 to about 8.0. In an embodiment, the present disclosure provides a composition comprising (a) about 1000 mM to about 6500 mM triethanolamine (TEA), (b) about 500 mM to about 2000 mM ionic components, and (c) a surfactant, wherein the composition has a pH of about 7.0 to about 8.0.

[0032] In embodiments, the present disclosure provides a composition comprising (a) about 1000 mM to about 6500 mM triethanolamine (TEA), (b) about 500 mM to about 2000 mM ionic components, (c) a surfactant, and (d) an ECL-labeled component, wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the present disclosure provides a composition comprising (a) about 1000 mM to about 6500 mM triethanolamine (TEA), (b) about 500 mM to about 2000 mM ionic components, (c) a surfactant, and (d) an ECL-labeled component, wherein the composition has a pH of about 7.0 to about 8.0.

[0033] In embodiments, the present disclosure provides a composition comprising (a) triethanolamine (TEA), (b) an ionic component, and (c) an alkyl ether polyethylene glycol (PEG), wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the present disclosure provides a composition comprising (a) triethanolamine (TEA), (b) an ionic component, and (c) an alkyl ether polyethylene glycol (PEG), wherein the composition has a pH of about 7.0 to about 8.0.

[0034] In embodiments, the present disclosure provides a composition comprising (a) triethanolamine (TEA), (b) an ionic component, (c) an alkyl ether-PEG, and (d) an ECL-labeled component, wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the present disclosure provides a composition comprising (a) triethanolamine (TEA), (b) an ionic component, (c) an alkyl ether-PEG, and (d) an ECL-labeled component, wherein the composition has a pH of about 7.0 to about 8.0.

[0035] In embodiments, the present disclosure provides a composition comprising: (a) an electrochemiluminescence (ECL) coreactant selected from N-tert-butyldiethanolamine (tBDEA), methyldiethanolamine (MDEA), 3-[bis-(2-hydroxy-ethyl)-amino]-propane-1-sulfonic acid (DEA-PS), and combinations thereof; (b) an ionic component; (c) a surfactant; and (d) a pH interfering component, wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the present disclosure provides a composition comprising: (a) an electrochemiluminescence (ECL) coreactant selected from N-tert-butyldiethanolamine (tBDEA), methyldiethanolamine (MDEA), 3-[bis-(2-hydroxy-ethyl)-amino]-propane-1-sulfonic acid (DEA-PS), and combinations thereof; (b) an ionic component; (c) a surfactant; and (d) a pH interfering component, wherein the composition has a pH of about 7.0 to about 8.0.

[0036] In embodiments, the present disclosure provides a composition comprising (a) an ECL coreactant selected from tBDEA, MDEA, DEA-PS, and combinations thereof, (b) an ionic component, (c) a surfactant, (d) a pH buffer component, and (e) an ECL labeling component, wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the present disclosure provides a composition comprising (a) an ECL coreactant selected from tBDEA, MDEA, DEA-PS, and combinations thereof, (b) an ionic component, (c) a surfactant, (d) a pH buffer component, and (e) an ECL labeling component, wherein the composition has a pH of about 7.0 to about 8.0.

[0037] As discussed herein, the ECL coreactants herein advantageously provide consistent ECL generation across different assay formats (e.g., washed and no-wash assays) and in combination with different classes of detergents (e.g., mild detergents that do not disrupt lipid bilayer membranes, as well as harsher detergents that can disrupt lipid bilayer membranes). Thus, compositions comprising the ECL coreactants herein (also referred to as "ECL read buffers") are useful in a wide range of ECL-based binding assays.

[0038] In embodiments, the ECL coreactant comprises a tertiary amine. In embodiments, the ECL coreactant comprises a tertiary alkylamine. In embodiments, the ECL coreactant comprises a tertiary hydroxyalkylamine. In embodiments, the ECL coreactant comprises a zwitterionic tertiary amine. In embodiments, the ECL coreactant comprises a secondary amine. In embodiments, the ECL coreactant is tributylamine (TBA), (dibutyl)aminoethanol (DBAE), (diethyl)aminoethanol (DEAE), triethanolamine (TEA), butyldiethanolamine (BDEA), propyldiethanolamine (PDEA), ethyldiethanolamine (EDEA), methyldiethanolamine (MDEA), tert-butyldiethanolamine (tBDEA), dibutylamine (DBA), butylethanolamine (BEA), diethanolamine (DEA), dibutylamine propylsulfonate (DBA-PS), dibutylamine butylsulfonate (DBA-BS), butylethanolamine propylsulfonate (BEA-PS), butylethanolamine butylsulfonate (BEA-BS), diethanolamine propylsulfonate (also known as 3-[bis-(2-hydroxyethyl)-amino]-propane-1-sulfonic acid, DEA-PS), or diethanolamine butylsulfonate (DEA-BS). The structures of exemplary ECL coreactants described herein are shown below. [ka]

[0039] Triethanolamine ECL coreactant The present disclosure provides compositions comprising an ECL coreactant. In embodiments, the ECL coreactant is triethanolamine (TEA). As discussed herein, TEA has been found to provide advantageous ECL-generating properties in no-wash binding assays. In assays in which a species of interest (e.g., an analyte or binding complex described herein) is captured and detected on a solid surface, TEA can distinguish between "free" ECL label (e.g., an analyte or binding complex) that is not part of the species being detected and "bound" ECL label (e.g., an analyte or binding complex) that is part of a surface-bound species. No-wash binding assays utilizing TEA as an ECL coreactant reduce ECL from the ECL label that is nonspecific to the species being detected, thereby reducing background ECL and increasing the signal-to-background ratio of the assay. In embodiments, no-wash assays using TEA as an ECL coreactant have a signal-to-background ratio that is 2-fold higher, 3-fold higher, 4-fold higher, 5-fold higher, or 10-fold higher than assays using tripropylamine (TPA) or piperazine-N,N'-bis(2-ethanesulfonic acid) (PIPES) as an ECL coreactant. In embodiments, no-wash assays using TEA as an ECL coreactant have a limit of detection that is 2-fold lower, 3-fold lower, 4-fold lower, 5-fold lower, 10-fold lower, 20-fold lower, or 40-fold lower than assays using TPA or PIPES as an ECL coreactant.

[0040] An additional advantage of TEA as an ECL coreactant is its insensitivity to sample matrix and / or interferents. This is particularly beneficial in the context of no-wash assays, where the reaction mixture may contain matrices derived from human or animal sources (e.g., containing proteins, cellular components and debris, culture media, etc.), which may also contain metabolites and / or drug interferents, such as acetaminophen, ibuprofen, naproxen, salicylic acid, and / or tolbutamine. In embodiments, TEA generates substantially the same ECL signal in a reaction mixture containing one or more sample matrices and / or one or more interferents as in a reaction mixture free of the sample matrix and / or interferents.

[0041] It has further been discovered that TEA offers the advantage of producing a consistent ECL signal when used in the absence of detergent or when combined with different types of detergents, such as the harsh and mild detergents described herein. As used herein, a "harsh" detergent is capable of disrupting, lysing, and / or dissolving lipid bilayer membranes (e.g., membranes of cells or extracellular vesicles (EVs)). In contrast, a "mild" detergent does not disrupt, lyse, or dissolve lipid bilayer membranes. In embodiments, a composition comprising TEA and a harsh detergent, when subjected to the same ECL-generating conditions (e.g., voltage waveform, type of electrode, amount of composition, amount of ECL label, etc.), produces a substantially similar ECL signal as a composition comprising the same components, except for the presence of a mild detergent instead of a harsh detergent. In embodiments, the harsh detergent is TRITON™ X-100, TRITON™ X-114, NP-40, IGEPAL® CA-630, 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), or sodium dodecyl sulfate (SDS). In embodiments, the mild detergent is BRIJ®, TWEEN®, PLURONIC®, or KOLLIPHOR® detergent, or an alkyl ether-PEG detergent such as PEG(18) tridecyl ether.

[0042] TEA has a pKa of approximately 7.7, allowing the pH of the composition to be maintained within a range of approximately 7.0 to approximately 8.0, a typical desired pH range for biological assays. Furthermore, TEA compositions having a pH of approximately 7.0 to approximately 8.0 have an ECL signal generated preferentially from the electrode-bound ECL label compared to the unbound ECL label described herein. Therefore, the compositions herein containing TEA have the added advantage of being pH compatible with biological assays and do not require additional pH buffering components, thereby simplifying the composition production process and reducing costs. In embodiments, the compositions containing TEA are substantially free of additional pH buffering components. Materials capable of acting as pH buffering components to maintain solutions within a specific pH range are known to those skilled in the art. For example, buffers capable of maintaining a pH of about 7.0 to about 8.0 include piperazine N,N'-bis(2-ethanesulfonic acid) (PIPES), cholamine chloride, 3-(N-morpholino)propanesulfonic acid (MOPS), N-[tris(hydroxymethyl)methyl]-2-aminoethanesulfonic acid (TES), 3-(N,N-bis[2-hydroxyethyl]amino)-2-hydroxypropanesulfonic acid (DIPSO), 4-(N-morpholino)butanesulfonic acid (MOBS), acetamidoglycine, N-[tris(hydroxymethyl)methyl] Examples of pH buffering components include, but are not limited to, N-(hydroxyethyl)piperazine-N'-2-hydroxypropanesulfonic acid (TAPSO), piperazine-1,4-bis(2-hydroxypropanesulfonic acid) dihydrate (POPSO), N-(hydroxyethyl)piperazine-N'-2-hydroxypropanesulfonic acid (HEPPSO), 3-[4-(2-hydroxyethyl)piperazin-1-yl]propane-1-sulfonic acid (HEPPS), tricine, glycinamide, N-(2-hydroxyethyl)piperazine-N'-(4-butanesulfonic acid) (HEPBS), and bicine. Further non-limiting examples of pH buffering components include tris(hydroxymethyl)aminomethane ("Tris"), phosphate, HEPES, glycylglycine ("GlyGly"), borate, acetate, and citrate.In embodiments, the TEA-containing composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, and citrate. In embodiments, the TEA-containing composition is substantially free of additional components having a pKa of about 7.0 to about 8.0.

[0043] Furthermore, many common pH buffering components have tertiary amines in their structure and can generate ECL. Exemplary pH buffering components that can act as ECL coreactants are provided in US Pat. No. 6,919,173 and include, but are not limited to, HEPES, POPSO, HEPPSO, and PIPES. In embodiments, the composition containing TEA is substantially free of additional ECL coreactants. In embodiments, the composition containing TEA is free of HEPES, POPSO, HEPPSO, and PIPES. In embodiments, the composition containing TEA is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES.

[0044] In an embodiment, the concentration of TEA in the composition is from about 500 mM to about 7000 mM, from about 800 mM to about 6800 mM, from about 1000 mM to about 6500 mM, from about 1000 mM to about 6400 mM, from about 1000 mM to about 6000 mM, from about 1000 mM to about 5500 mM, from about 1100 mM to about 5000 mM, or from about The concentration is 1100 mM to about 4800 mM, about 1100 mM to about 4000 mM, about 1100 mM to about 3500 mM, about 1100 mM to about 3200 mM, about 1100 mM to about 3000 mM, about 1100 mM to about 2500 mM, about 1200 mM to about 2400 mM, or about 1200 mM to about 1600 mM. In embodiments, the concentration of TEA in the composition is about 1000 mM, about 1100 mM, about 1200 mM, about 1300 mM, about 1400 mM, about 1500 mM, about 1600 mM, about 1700 mM, about 1800 mM, about 1900 mM, about 2000 mM, about 2100 mM, about 2200 mM, about 2300 mM, about 2400 mM, about 2500 mM, about 2600 mM, about 2700 mM, about 2800 mM, about 2900 mM, about 3000 mM, about 3100 mM, about 3200 mM, about 3300 mM, about 3400 mM, about 3500 mM, about 3600 mM, about 3700 mM, about 3800 mM, about 3900 mM, about 4 0mM, approx. 2400mM, approx. 2500mM, approx. 2600mM, approx. 2700mM, approx. 2800mM, approx. 2900mM, approx. 3000mM, approx. 310 0mM, approx. 3200mM, approx. 3300mM, approx. 3400mM, approx. 3500mM, approx. 3600mM, approx. 3700mM, approx. 3800mM, approx. 390 0 mM, about 4000 mM, about 4100 mM, about 4200 mM, about 4300 mM, about 4400 mM, about 4500 mM, about 4600 mM, about 4700 mM, about 4800 mM, about 4900 mM, about 5000 mM, about 5100 mM, about 5200 mM, about 5300 mM, about 5400 mM, about 550 0 mM, about 5600 mM, about 5700 mM, about 5800 mM, about 5900 mM, about 6000 mM, about 6100 mM, about 6200 mM, about 6300 mM, about 6400 mM, about 6500 mM, about 6600 mM, about 6700 mM, about 6800 mM, about 6900 mM, or about 7000 mM. In embodiments, the concentration of TEA in the composition is at least about 1000 mM, at least about 1200 mM, at least about 1600 mM, at least about 1800 mM, at least about 2000 mM, at least about 2500 mM, at least about 3000 mM, at least about 3500 mM, at least about 4000 mM, at least about 4500 mM, at least about 5000 mM, at least about 5500 mM, or at least about 6000 mM.Surprisingly, the TEA concentration in the composition positively correlated with the intensity of the ECL signal generated, which was unexpected because other ECL coreactants, such as PIPES (both PIPES and TEA were expected to behave similarly to TEA due to their ability to confine ECL near the electrode as described herein), exhibited decreased ECL generation with increasing ECL coreactant concentration (see, e.g., Figures 3A and 3B). Thus, the TEA compositions provided herein can preferentially and consistently generate ECL signal from electrode-bound ECL labels over a wide concentration range, e.g., from about 1000 mM to about 6500 mM, relative to the unbound ECL labels described herein. Consistency in electrode-bound ECL generation reduces variability in ECL generation in ECL-based assays, e.g., in washed or non-washed assay formats. ECL coreactants (e.g., TEA) that can be used at high concentrations offer advantages in no-wash assays by minimizing dilution of the sample and / or assay mixture, avoiding perturbation of the binding equilibrium and kinetics of the assay components, and thus maximizing the ECL signal. ECL coreactants (e.g., TEA) that can be used at high concentrations are also useful in assays with lower affinity binding and / or detection reagents and offer improved sensitivity compared to ECL coreactants (e.g., PIPES) that cannot be used at high concentrations.

[0045] Alkyldiethanolamine / zwitterionic tertiary amine ECL coreactants The present disclosure further provides compositions comprising an alkyldiethanolamine ECL coreactant and / or a zwitterionic tertiary amine ECL coreactant. In embodiments, the alkyldiethanolamine is butyldiethanolamine (BDEA), propyldiethanolamine (PDEA), ethyldiethanolamine (EDEA), methyldiethanolamine (MDEA), or tert-butyldiethanolamine (tBDEA). In embodiments, the alkyldiethanolamine is N-tert-butyldiethanolamine (tBDEA) or methyldiethanolamine (MDEA). In embodiments, the zwitterionic tertiary amine ECL coreactant is dibutylamine propylsulfonate (DBA-PS), dibutylamine butylsulfonate (DBA-BS), butylethanolamine propylsulfonate (BEA-PS), butylethanolamine butylsulfonate (BEA-BS), diethanolamine propylsulfonate (also known as 3-[bis-(2-hydroxyethyl)-amino]-propane-1-sulfonic acid, DEA-PS), or diethanolamine butylsulfonate (DEA-BS). In embodiments, the zwitterionic tertiary amine ECL coreactant is DEA-PS. tBDEA, MDEA, and DEA-PS have been found to advantageously exhibit consistent ECL generation properties when used in the absence of a surfactant or when combined with different types of surfactants, such as the harsh and mild surfactants described herein. In embodiments, a composition comprising tBDEA, MDEA, and / or DEA-PS and a harsh surfactant generates a substantially similar ECL signal when subjected to the same ECL-generating conditions (e.g., voltage waveform, type of electrode, amount of composition, amount of ECL label, etc.) as a composition comprising the same components, except for the presence of a mild surfactant instead of the harsh surfactant. In embodiments, the harsh surfactant is TRITON™ X-100, TRITON™ X-114, NP-40, IGEPAL® CA-630, 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), or sodium dodecyl sulfate (SDS).In embodiments, the mild surfactant is a BRIJ®, TWEEN®, PLURONIC®, or KOLLIPHOR® surfactant, or an alkyl ether-PEG surfactant such as PEG(18) tridecyl ether.

[0046] In embodiments, the concentration of the alkyldiethanolamine or zwitterionic tertiary amine in the composition is from about 10 mM to about 500 mM, from about 20 mM to about 400 mM, from about 50 mM to about 250 mM, or from about 100 mM to about 200 mM. In embodiments, the concentration of the alkyldiethanolamine zwitterionic tertiary amine in the composition is about 10 mM, about 20 mM, about 30 mM, about 40 mM, about 50 mM, about 60 mM, about 70 mM, about 80 mM, about 90 mM, about 100 mM, about 110 mM, about 120 mM, about 130 mM, about 140 mM, about 150 mM, about 160 mM, about 170 mM, about 180 mM, about 190 mM, about 200 mM, about 250 mM, about 300 mM, about 350 mM, about 400 mM, about 450 mM, or about 500 mM. In embodiments, the alkyldiethanolamine is tBDEA. In embodiments, the alkyldiethanolamine is MDEA. In embodiments, the alkyldiethanolamine is a combination of tBDEA and MDEA. In embodiments, the zwitterionic tertiary amine is DEA-PS. In embodiments, the composition comprises a combination of two or more of tBDEA, MDEA, and DEA-PS.

[0047] In embodiments, compositions comprising alkyldiethanolamines and / or zwitterionic tertiary amines (e.g., tBDEA, MDEA, and / or DEA-PS) further comprise a pH buffering component. In embodiments, the pH buffering component has a pKa of about 7.0 to about 8.0. In embodiments, the pH buffering component can maintain the pH of the composition at about 7.0 to about 8.5, about 7.2 to about 8.0, or about 7.4 to about 7.9. In embodiments, the pH buffering component comprises Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, PIPES, MOPS, TES, DIPSO, MOBS, TAPSO, POPSO, HEPPSO, HEPPS, tricine, glycinamide, HEPBS, bicine, or a combination thereof. In embodiments, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the pH buffering component comprises Tris. In embodiments, the pH buffering component comprises phosphate.

[0048] In one embodiment, the concentration of the pH buffering component in the composition is about 10 mM to about 800 mM, about 20 mM to about 600 mM, about 50 mM to about 400 mM, about 100 mM to about 300 mM, about 120 mM to about 280 mM, or about 150 mM to about 250 mM. In another embodiment, the concentration of the pH buffering component in the composition is about 50 mM, about 100 mM, about 150 mM, about 200 mM, about 250 mM, about 300 mM, about 350 mM, about 400 mM, about 450 mM, or about 500 mM.

[0049] Ion components In embodiments, the compositions herein include an ionic component. The ionic component, such as a salt, dissociates into ions in solution. It has been found that a high ionic concentration can advantageously reduce non-specific binding of the ECL label with the ECL coreactant. Non-limiting examples of ionic components include the cation Li + , Na + , K. + , Rb + , Cs + , Mg +2 , Ca +2 , and NH4 +and / or anion F - , Cl - , Br - , I - In embodiments, the ionic component may be Li, phosphate, sulfate, or borate. + , Na + , or K + In an embodiment, the ionic component comprises Cl - In embodiments, the ionic component comprises lithium chloride (LiCl), sodium chloride (NaCl), potassium chloride (KCl), or a combination thereof. In embodiments, the ionic component comprises NaCl. In embodiments, the ionic component comprises KCl.

[0050] In an embodiment, the concentration of the ionic component in the composition is about 100 mM to about 2000 mM, about 200 mM to about 1800 mM, about 300 mM to about 1700 mM, about 400 mM to about 1600 mM, about 500 mM to about 1500 mM, about 600 mM to about 1200 mM, about 700 mM to about 1000 mM, or about 800 mM to about 900 mM. In embodiments, the concentration of the ionic component in the composition is about 500 mM, about 550 mM, about 600 mM, about 650 mM, about 700 mM, about 750 mM, about 800 mM, about 850 mM, about 900 mM, about 950 mM, about 1000 mM, about 1100 mM, about 1200 mM, about 1300 mM, about 1400 mM, or about 1500 mM.

[0051] In embodiments, the composition comprises about 100 mM to about 2000 mM, about 200 mM to about 1800 mM, about 300 mM to about 1700 mM, about 400 mM to about 1600 mM, about 500 mM to about 1500 mM, about 600 mM to about 1200 mM, about 700 mM to about 1000 mM, or about 800 mM to about 900 mM NaCl. In embodiments, the composition comprises about 100 mM to about 2000 mM, about 200 mM to about 1800 mM, about 300 mM to about 1700 mM, about 400 mM to about 1600 mM, about 500 mM to about 1500 mM, about 600 mM to about 1200 mM, about 700 mM to about 1000 mM, or about 800 mM to about 900 mM KCl. In embodiments, the composition comprises about 100 mM to about 2000 mM, about 200 mM to about 1800 mM, about 300 mM to about 1700 mM, about 400 mM to about 1600 mM, about 500 mM to about 1500 mM, about 600 mM to about 1200 mM, about 700 mM to about 1000 mM, or about 800 mM to about 900 mM LiCl.

[0052] In embodiments, the composition has an ionic strength of about 0.2 M to about 2 M, about 0.5 M to about 1.5 M, about 0.75 M to about 1.25 M, or about 0.8 M to about 1.0 M. In embodiments, the composition has an ionic strength of about 0.3 M or more, about 0.5 M or more, about 0.8 M or more, or about 1.0 M or more. In embodiments, the composition comprises chloride ions, and the concentration of chloride ions is about 0.3 M or more, about 0.5 M or more, about 0.8 M or more, or about 1.0 M or more.

[0053] In embodiments, non-specific binding (NSB) in an immunoassay using ECL as the assay readout is lower for a composition containing an ionic component compared to an otherwise identical composition that does not contain the ionic component.

[0054] surfactants It has been unexpectedly discovered that when using compositions provided herein containing, for example, TEA, tBDEA, MDEA, and / or DEA-PS as ECL coreactants, the ECL generation properties of the compositions are substantially unaffected by the presence, concentration, or structure of surfactants in the compositions. In contrast, TPA-based compositions generally require the presence of surfactants for optimal signal generation. In particular, TPA provides optimal ECL generation in the presence of surfactants containing aromatic moieties, such as the phenol ether moiety in TRITON™ X-100.

[0055] In embodiments, the compositions herein are substantially free of surfactants. In embodiments, the compositions herein contain a surfactant. In embodiments, the compositions herein contain a surfactant at a concentration below the critical micelle concentration (CMC) of the surfactant. The CMC is the concentration of the surfactant at which micelles are formed, and any additional amount of surfactant added to the composition above the CMC will be incorporated into the micelles. The CMC of a surfactant can be determined by one skilled in the art, for example, using the titration method described in Wu et al., Anal Chem 92(6):4259-4265 (2020), and / or using a device such as a dynamic contact angle measurement apparatus and / or a tensiometer.

[0056] In embodiments, the compositions herein comprise a non-ionic surfactant. In embodiments, the compositions herein comprise an ionic surfactant. Non-ionic surfactants include NONIDET™ (octylphenoxypolyethoxyethanol), BRIJ™ (polyoxyethylene fatty acid ether), TRITON™ (2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol), TWEEN™ (polysorbate), KOLLIPHOR™ (polyoxyl castor oil), THESIT™ (polyethylene glycol dodecyl ether), LUBROL™ (polyoxyethylene alkyl ether), GENAPOL™ (isotridecyl alcohol polyisoprene). glycol ethers), PLURONIC® (poloxamer block copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) arranged as PEO-PPO-PEO), TETRONIC® (poloxamine block copolymers of PEO-PPO), SYNPERONIC® (block copolymers of poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG) arranged as PEG-PPG-PEG), and SPAN® (sorbitan). Specific examples of nonionic surfactants include, for example, KOLLIPHOR® P-407 (PEG 101 -PPG 56 -PEG 101 , also known as Poloxamer 407), PLURONIC® P-123 (PEO 18 -PPO 72 -PEO 18 ), PLURONIC® L-121 (PEG5-PPG 68 -PEG5), PLURONIC (registered trademark) 31R1 (PPO 26 -PEO5-PPO 26), TETRONIC® 701 (ethylenediaminetetrakis(propoxylate block ethoxylate) tetrol), BRIJ® L4 (polyethylene glycol dodecyl ether), BRIJ® 58 (polyethylene glycol hexadecyl ether), TWEEN® 20 (polysorbate 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, and alkyl ether-polyethylene glycols (PEGs) such as PEG(10) tridecyl ether, PEG(12) tridecyl ether, and PEG(18) tridecyl ether.

[0057] In embodiments, the surfactant comprises a phenol ether. In embodiments, the surfactant is 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100). In the context of the surfactants described herein, TRITON™ X-100 is a "harsh" surfactant that can disrupt, dissolve, and / or dissolve lipid bilayer membranes, e.g., membranes of cells or extracellular vesicles (EVs).

[0058] In embodiments, the surfactant does not contain an aromatic moiety. In embodiments, the surfactant does not contain a phenol ether. In embodiments, the surfactant does not disrupt, lyse, or dissolve lipid bilayer membranes, e.g., membranes of cells or extracellular vesicles (EVs). Such surfactants may be referred to as "mild" surfactants. Examples of mild surfactants include the classes of surfactants known by the trade names BRIJ®, TWEEN®, PLURONIC®, or KOLLIPHOR®. In embodiments, the surfactant does not contain an ester linkage. In embodiments, the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20, 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the surfactant is an alkyl ether-polyethylene glycol (PEG). In embodiments, the alkyl ether-polyethylene glycol (PEG) is PEG(10) tridecyl ether, PEG(12) tridecyl ether, PEG(18) tridecyl ether, or a combination thereof. In embodiments, the surfactant is PEG(18) tridecyl ether.

[0059] As described herein, the compositions herein advantageously provide consistent ECL signal generation in the presence of different types of surfactants, e.g., harsh and mild surfactants described herein. In embodiments, a composition comprising TEA, tBDEA, MDEA, DEA-PS, or a combination thereof and a harsh surfactant, when subjected to the same ECL-generating conditions (e.g., voltage waveform, type of electrode, amount of composition, amount of ECL label, etc.), generates substantially similar ECL signals as a composition comprising the same components, except for the presence of a mild surfactant instead of the harsh surfactant. In embodiments, a composition comprising TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof and a harsh surfactant, when subjected to the same ECL-generating conditions (e.g., voltage waveform, type of electrode, amount of composition, amount of ECL label, etc.), generates substantially similar ECL signals as a composition comprising the same components, except for the presence of a mild surfactant instead of the harsh surfactant. In embodiments, the harsh surfactant is TRITON™ X-100. In embodiments, the mild surfactant is a BRIJ®, TWEEN®, PLURONIC®, or KOLLIPHOR® surfactant, or an alkyl ether-PEG surfactant such as PEG(18) tridecyl ether.

[0060] In embodiments, the concentration of surfactant in the composition is such that the composition has an air-liquid surface tension of about 50 dynes / cm or less, about 40 dynes / cm or less, or about 35 dynes / cm or less. In embodiments, the surfactant is present in the composition at its cmc, at about 2 times its cmc or more, or at about 5 times its cmc or more.

[0061] In embodiments, the surfactant is about 0.1% (v), about 0.5% (v / v), about 1% (v / v), about 2% (v / v), about 5% (v / v), about 7% (v / v), or about 10% (v / v) of the composition. In embodiments, the concentration of the surfactant in the composition is about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM. In embodiments, the concentration of the surfactant in the composition is about 0.1 mM, about 0.2 mM, about 0.3 mM, about 0.4 mM, about 0.5 mM, about 0.6 mM, about 0.7 mM, about 0.8 mM, about 0.9 mM, about 1 mM, about 2 mM, about 3 mM, about 4 mM, about 5 mM, about 6 mM, about 7 mM, about 8 mM, about 9 mM, or about 10 mM.

[0062] In embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100). In embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM Poloxamer 407 (KOLLIPHOR™ P-407). In embodiments, the composition comprises from about 0.1 mM to about 20 mM, from about 0.1 mM to about 10 mM, from about 0.5 mM to about 8 mM, from about 0.75 mM to about 6 mM, or from about 1 mM to about 5 mM PEO. 18 -PPO 72 -PEO 18 (PLURONIC® P-123). In embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM PEG5-PPG. 68 In embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM PPO. 26 -PEO5-PPO 26(PLURONIC® 31R1). In embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701). In embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM polyethylene glycol dodecyl ether (BRIJ® L4). In an embodiment, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM polyethylene glycol hexadecyl ether (BRIJ® 58). In an embodiment, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM polysorbate 20 (TWEEN® 20). In some embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM of 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate. In some embodiments, the composition comprises about 0.1 mM to about 20 mM, about 0.1 mM to about 10 mM, about 0.5 mM to about 8 mM, about 0.75 mM to about 6 mM, or about 1 mM to about 5 mM of alkyl ether-PEG. In some embodiments, the alkyl ether-PEG is PEG(18) tridecyl ether.

[0063] pH In embodiments, the compositions herein have a pH of about 6.0 to about 9.0, about 7.0 to about 8.0, about 7.2 to about 7.6, about 7.5 to about 7.8, about 7.4 to about 7.9, about 7.0, about 7.1, about 7.2, about 7.3, about 7.4, about 7.5, about 7.6, about 7.7, about 7.8, about 7.9, or about 8.0. In embodiments, the pH of the composition is about 7.5. In embodiments, the pH of the composition is about 7.8.

[0064] In embodiments, the composition comprising TEA has a pH of about 7.0 to about 8.0, about 7.4 to about 7.9, or about 7.5 to about 7.8, and is substantially free of additional pH buffering components. In embodiments, the composition comprising TEA has a pH of about 7.0 to about 8.0, about 7.4 to about 7.9, or about 7.5 to about 7.8, and is substantially free of additional components with a pKa of about 7.0 to about 8.0. In embodiments, the composition comprising TEA is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, and citrate. In embodiments, the composition comprising TEA is free of HEPES, POPSO, HEPPSO, and PIPES. In embodiments, the composition comprising TEA is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES.

[0065] ECL labeled component In embodiments, the compositions herein include an ECL-labeled component. In embodiments, the ECL coreactant compositions provided herein, for example, including TEA, tBDEA, MDEA, and / or DEA-PS and an ECL-labeled component, are capable of generating ECL. In embodiments, the ECL-labeled component includes an ECL label. In embodiments, the ECL-labeled component includes a detection reagent. In embodiments, the ECL-labeled component includes a binding partner for the detection reagent.

[0066] In embodiments, the ECL label component is a detection reagent comprising an ECL label. In embodiments, the detection reagent comprises an antibody or antigen-detecting fragment thereof, an antigen, a ligand, a receptor, an oligonucleotide, a hapten, an epitope, a mimotope, or an aptamer. In embodiments, the detection reagent is an antibody or a variant thereof, including its antigen / epitope-detecting portion, an antibody fragment or derivative, an antibody analog, an engineered antibody, or a substance that binds to an antigen in a manner similar to an antibody. In embodiments, the detection reagent comprises at least one heavy or light chain complementarity-determining region (CDR) of an antibody. In embodiments, the detection reagent comprises at least two CDRs from one or more antibodies. In embodiments, the detection reagent is an antibody or an antigen-detecting fragment thereof. In embodiments, the detection reagent is covalently linked to the ECL label via a conjugated linker. Methods for conjugating labels, such as ECL labels, to detection reagents are known to those skilled in the art.

[0067] In embodiments, the ECL labeled component is a binding partner of the detection reagent. In embodiments, the ECL labeled component and the detection reagent form a complex that can be detected by ECL. In embodiments, the ECL labeled component and the detection reagent comprise a receptor-ligand pair, an antigen-antibody pair, a hapten-antibody pair, an epitope-antibody pair, a mimotope-antibody pair, an aptamer-target molecule pair, or an intercalator-target molecule pair. In embodiments, the ECL labeled component and the detection reagent comprise complementary oligonucleotides. In embodiments, the ECL labeled component and the detection reagent comprise a biotin-avidin or biotin-streptavidin pair.

[0068] In embodiments, the ECL-labeled component is an oligonucleotide. In embodiments, the ECL-labeled oligonucleotide and the detection reagent comprise complementary oligonucleotides, and in other embodiments, the ECL-labeled oligonucleotide is the detection reagent. In embodiments, the binding reagent comprises an oligonucleotide and the ECL-labeled oligonucleotide is complementary to that oligonucleotide. In embodiments, the binding partner comprises an oligonucleotide and the ECL-labeled oligonucleotide is complementary to the binding partner oligonucleotide. In embodiments, the binding partner is an analyte oligonucleotide and the ECL-labeled oligonucleotide is complementary to the analyte oligonucleotide. In embodiments, the binding partner of the ECL-labeled oligonucleotide is the analyte oligonucleotide, the ECL-labeled oligonucleotide is complementary to a portion of the analyte oligonucleotide, and the binding reagent is a capture oligonucleotide that is complementary to a different portion of the analyte oligonucleotide. In embodiments, the ECL-labeled component is an oligonucleotide probe complementary to an extension primer attached to a detection reagent (e.g., a detection antibody) that binds to a target analyte, such as a peptide or protein. In embodiments, the binding reagent is streptavidin and the binding complex comprising the oligonucleotide is a complex of a biotinylated capture antibody, a peptide, and a second antibody comprising an oligonucleotide primer (see, for example, but not limited to, Figure 20).

[0069] In one embodiment, the ECL-labeled oligonucleotide is a probe. In another embodiment, the ECL-labeled oligonucleotide is a probe that is 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, or more nucleotides in length, or a range defined by any two of the preceding values. In one embodiment, the ECL-labeled oligonucleotide probe comprises a stem-loop or hairpin structure, an ECL label, and a quenching moiety, the quenching moiety being adjacent to the ECL label and quenching the ECL label when the ECL-labeled oligonucleotide probe is in the stem-loop or hairpin configuration, but not when the stem-loop or hairpin structure is in the open configuration. In another embodiment, the ECL-labeled oligonucleotide probe having a stem-loop or hairpin structure is an ECL-labeled molecular beacon probe. In embodiments, the binding partner of an ECL-labeled hairpin or molecular beacon oligonucleotide probe is an analyte oligonucleotide, the ECL-labeled oligonucleotide probe is complementary to a portion of the analyte oligonucleotide, and the binding reagent is a capture oligonucleotide that is complementary to a different portion of the analyte oligonucleotide (see, for example, but not limited to, Figure 14). In embodiments, the ECL-labeled molecular beacon probe is complementary to an extension primer attached to a detection reagent (e.g., a detection antibody) that binds to a target analyte, such as a peptide or protein (see, for example, but not limited to, Figure 20).

[0070] ECL-labeled molecular beacon probes can be prepared using conventional methods known in the art for conventional molecular beacon probes. In embodiments, the probes can have a probe sequence of 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 bases in length, or a range defined by any two of the preceding values, e.g., 10-30, 10-15, or 15-30 bases, and 5' and 3' stem complement sequences of 5, 6, 7, 8, 9, 10, 11, 12, or 13 bases in length, or a range defined by any two of the preceding values, e.g., 5-8 bases in length. In embodiments, the stem is 5-8 base pairs in length and has a very high GC content (75-100%). In embodiments, ECL-labeled molecular beacon probes are labeled at the 5' and 3' ends with an ECL label and a quenching moiety, e.g., a 5'ECL label and a 3' quenching moiety, or vice versa. A conventional molecular beacon probe design tool can be found at www.molecular-beacons.org / MB_SC_design. In embodiments, the use of short probe sequences reduces the need for stem-loop structures and allows for more effective static quenching by contact. To achieve these goals, molecular beacons based on LNA sequences have proven useful. An example is found in Eboigbodin KE, et al., "Rapid and sensitive real-time assay for the detection of respiratory syncytial virus using RT-SIBA," BMC Infect Dis. 2017 (incorporated herein by reference in its entirety). An example of such a probe is / 56-ROXN / +CA+A+TA+T+T+GA+GA+TA / 3IABkFQ / .In embodiments, ECL-labeled oligonucleotide probes may be designed using double-strand stabilization technology (Minor Groove Binder, MGB™), BHQplus® probes (Biosearch Technology), to allow for shorter probe design. Minor Groove Binders are available as phosphoramidites, and CPG allows for their incorporation into the oligonucleotide synthesis process during probe synthesis (IDT). One embodiment is to use an MGB-CPG support, add a quencher molecule, then add the sequence and the final 5' amino group, and label with the ECL moiety. Alternatively, they may be added post-synthetically by performing NHS-ester-based labeling of amino groups introduced during oligonucleotide synthesis. Minor Groove Binders include those described in U.S. Pat. No. 9,334,495, incorporated herein by reference in its entirety.

[0071] In embodiments, the ECL-labeled oligonucleotide probe comprises an ECL label and a quencher, which are sufficiently close to each other on the probe when the probe is in a linear configuration (e.g., not a stem-loop or hairpin configuration) such that the quenching moiety quenches the ECL signal regardless of whether the probe is hybridized to a complementary oligonucleotide (e.g., as shown in Figure 21). Such ECL-labeled probes can be made using conventional methods known in the art, such as those used to design TaqMan® probes. In embodiments, the ECL-labeled oligonucleotide probe is 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, or more nucleotides in length, or a range defined by any two of the preceding values. In embodiments, the ECL-labeled probe is labeled at the 5' and 3' ends with an ECL label and a quenching moiety, for example, a 5' ECL label and a 3' quenching moiety, or vice versa. In embodiments, one or both of the ECL labeling moiety and the quenching moiety are attached at a position other than the 5' or 3' end of the oligonucleotide. In embodiments, the quenching moiety is at the 5' end of the oligonucleotide.

[0072] In embodiments, the ECL-labeled oligonucleotide probe is DNA, RNA, a mixture of both, and / or contains one or more modified nucleic acids. In embodiments, the ECL-labeled oligonucleotide contains one or more nucleotides that are resistant to enzymatic cleavage, for example, by an exonuclease or endonuclease. In embodiments, the resistant nucleotide(s) is / are a peptide nucleic acid or other resistant nucleic acid mimic known in the art. In embodiments, only a portion of the ECL-labeled oligonucleotide probe is resistant, with the quenching site located on the non-resistant portion (e.g., the 5' portion) while the ECL label is located on the resistant portion (e.g., the central portion and / or the 3' portion). Therefore, when an enzyme (e.g., a 5' exonuclease) cleaves the ECL-labeled oligonucleotide, the quenching site is released into solution, and the resistant portion of the ECL-labeled probe containing the ECL label remains hybridized to a complementary oligonucleotide (e.g., a binding partner and / or oligonucleotide of a binding complex). In embodiments, the ECL-labeled oligonucleotide probe comprises a feature, such as, but not limited to, a sequence and / or type of nucleotide (e.g., RNA) recognized by an enzyme that cleaves the ECL-labeled oligonucleotide probe only when hybridized to a complementary oligonucleotide (e.g., an oligonucleotide of a binding partner and / or binding complex) (e.g., as shown in Figure 21). In embodiments, the enzyme is a restriction endonuclease, optionally a nicking endonuclease, and the feature is a sequence recognized by the restriction endonuclease, or the enzyme is an RNasH2 enzyme and the feature is one or more RNA nucleotides. In embodiments, the ECL-labeled oligonucleotide probe comprises a feature proximal to the quenching site such that when the enzyme cleaves the ECL-labeled oligonucleotide probe, the quenching site is released into solution, and the ECL-labeled probe, including the ECL label, remains hybridized to a complementary oligonucleotide (e.g., an oligonucleotide of a binding partner and / or binding complex).

[0073] In some embodiments, multiple ECL-labeled oligonucleotide probes can be used. In some embodiments, multiple ECL-labeled oligonucleotide probes each have a different sequence complementary to the sequence of a different target oligonucleotide (e.g., an oligonucleotide on a binding reagent, detection reagent, binding partner, and / or oligonucleotide analyte), allowing specific hybridization of the ECL-labeled oligonucleotide probe to its respective target oligonucleotide. In some embodiments, the target oligonucleotides are localized at known locations on a substrate so that the presence of an ECL signal at a known location can be correlated with the presence of the target oligonucleotide (e.g., an oligonucleotide on a binding reagent, detection reagent, binding partner, and / or oligonucleotide analyte). In some embodiments, multiple different target oligonucleotides are localized in multiple spots on the bottom surface of a culture plate well, with each target oligonucleotide having a specific sequence being localized in a specific, predefined spot. In some embodiments, each spot contains a specific immobilized binding reagent (e.g., a capture oligonucleotide) that is different from the binding reagents immobilized in other spots on the substrate surface (e.g., the bottom of the plate well). Each spot can be coated with an electrode layer to which the binding reagent is immobilized. In this way, multiplexed reactions can be performed using multiple ECL-labeled oligonucleotide probes. In some embodiments, the multiplex reaction utilizes 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or more different ECL-labeled oligonucleotide probes, each having a different oligonucleotide sequence complementary to a different target oligonucleotide. In embodiments, the ECL labels are those described herein, e.g., in the following paragraphs.In embodiments, the quencher moiety is selected from the group consisting of ATTO 540Q, ATTO 575Q, ATTO 580Q, ATTO 612Q, Iowa Black FQ, Iowa Back RQ, QSY 21, IRDye QC-1, BHQ0, BHQ1, BHQ-2, BHQ-3, Dabcyl, QSY 7, QSY 9, QSY 21, QSY 35, QXL 490, QXL 520, QXL 570, and QXL 670. In embodiments, the quencher moiety is an anti-ECL label antibody, or a binding fragment thereof. In embodiments, the quencher moiety is ferrocene or iron tris-bipyridine. In embodiments, the ECL label has Formula II: In embodiments, the ECL label has Formula II below and the quencher moiety is Iowa Black: In embodiments, the ECL label has Formula II below and the quencher moiety is Dabcyl:

[0074] In embodiments, the ECL label comprises an electrochemiluminescent organometallic complex. In embodiments, the electrochemiluminescent organometallic complex comprises ruthenium, osmium, iridium, rhenium, and / or a lanthanide metal. In embodiments, the ECL label comprises ruthenium. In embodiments, the electrochemiluminescent organometallic complex comprises a substituted or unsubstituted bipyridine or a substituted or unsubstituted phenanthroline. In embodiments, the ECL label comprises a substituted bipyridine. In embodiments, the ECL label comprises ruthenium(II) tris-bipyridine. In embodiments, the ECL label comprises an organometallic complex comprising at least one substituted bipyridine ligand, wherein the substituted bipyridine ligand comprises at least one sulfonate group. In embodiments, the ECL label comprises an organometallic complex comprising at least two substituted bipyridine ligands, wherein each substituted bipyridine ligand comprises at least one sulfonate group. In embodiments, the substituted bipyridine ligand comprising at least one sulfonate group is represented by Formula I: [ka] (I)

[0075] In embodiments, the ECL label comprises three ligands, a first ligand being a compound of Formula I and a second ligand comprising a bipyridine having at least one substituent covalently linked to a detection reagent. In embodiments, the ECL label comprises an organometallic complex comprising three ligands, two of which are each a compound of Formula I and a third ligand comprising a bipyridine having at least one substituent covalently linked to a detection reagent.

[0076] In embodiments, the first detectable label has Formula II: [ka] (II)

[0077] Further exemplary ECL labels can be found in US 5,714,089, US 6,136,268, US 6,316,607, US 6,468,741, US 6,479,233, US 6,808,939, and US 9,499,573, each of which is incorporated herein by reference in its entirety.

[0078] TEA composition In an embodiment, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA and about 500 mM to about 1500 mM of an ionic component, wherein the composition has a pH of about 7.0 to about 8.0, and the ionic component is NaCl, KCl, or LiCl. In an embodiment, the composition is substantially free of an additional pH buffer component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL label component. In an embodiment, the ECL label component is a detection reagent comprising an ECL label.

[0079] In an embodiment, the present disclosure provides a composition comprising about 1100 mM to about 3500 mM TEA and about 600 mM to about 1200 mM of an ionic component, wherein the composition has a pH of about 7.0 to about 8.0, and the ionic component is NaCl, KCl, or LiCl. In an embodiment, the composition is substantially free of an additional pH buffer component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL label component. In an embodiment, the ECL label component is a detection reagent comprising an ECL label.

[0080] In an embodiment, the present disclosure provides a composition comprising about 1200 mM to about 1600 mM TEA and about 700 mM to about 900 mM of an ionic component, wherein the composition has a pH of about 7.0 to about 8.0, and the ionic component is NaCl, KCl, or LiCl. In an embodiment, the composition is substantially free of additional pH buffer components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL label component. In an embodiment, the ECL label component is a detection reagent comprising an ECL label. In an embodiment, the composition comprises about 1200 mM TEA and about 850 mM NaCl. In embodiments, the composition comprises about 1600 mM TEA and about 850 mM NaCl. In embodiments, the composition comprises about 1200 mM TEA and about 850 mM KCl. In embodiments, the composition comprises about 1600 mM TEA and about 850 mM KCl. In embodiments, the composition comprises about 1200 mM TEA and about 850 mM LiCl. In embodiments, the composition comprises about 1600 mM TEA and about 850 mM LiCl. In embodiments, the composition has a pH of about 7.5. In embodiments, the composition has a pH of about 7.8.

[0081] In embodiments, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 500 mM to about 1500 mM ionic components, and about 0.1 mM to about 10 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0082] In embodiments, the present disclosure provides a composition comprising about 1100 mM to about 3500 mM TEA, about 600 mM to about 1200 mM ionic components, and about 0.5 mM to about 8 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26-PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0083] In embodiments, the present disclosure provides a composition comprising about 1200 mM to about 1600 mM TEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.4 to about 7.9, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0084] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.4 to about 7.9, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0085] In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.4 to about 7.9, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0086] In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.4 to about 7.9, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0087] In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.4 to about 7.9, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0088] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM to about 5 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0089] In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the ionic component being NaCl, KCl, or LiCl, and the surfactant being 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0090] In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM to about 5 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0091] In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0092] In embodiments, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 850 mM NaCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0093] In embodiments, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 850 mM KCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0094] In embodiments, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 850 mM LiCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0095] In an embodiment, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and the surfactant is 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100). In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL label component. In an embodiment, the ECL label component is a detection reagent comprising an ECL label.

[0096] In an embodiment, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 700 mM to about 900 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0097] In an embodiment, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of an additional pH buffer component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL label component. In an embodiment, the ECL label component is a detection reagent comprising an ECL label.

[0098] In embodiments, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.5, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0099] In embodiments, the present disclosure provides a composition comprising about 1000 mM to about 6500 mM TEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.8, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition is substantially free of additional pH buffering components. In an embodiment, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of any of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeled component, hi embodiments, the ECL labeled component is a detection reagent that comprises an ECL label.

[0100] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5.In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In embodiments, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0101] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5.In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In embodiments, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0102] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5.In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In embodiments, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0103] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM NaCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM NaCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0104] In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM NaCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO, and the like. 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM NaCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0105] In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM NaCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM NaCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0106] In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM NaCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM NaCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0107] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM KCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM KCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0108] In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM KCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM KCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0109] In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM KCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM KCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0110] In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM KCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate) tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM KCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0111] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM LiCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM LiCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0112] In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM LiCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM LiCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0113] In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM LiCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate) tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM LiCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0114] In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM LiCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO, and PEG-100. 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM LiCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the composition is substantially free of an additional pH buffering component. In an embodiment, the composition is substantially free of an additional component having a pKa of about 7.0 to about 8.0. In an embodiment, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0115] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In embodiments, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeling component.In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0116] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In embodiments, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeling component.In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0117] In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1200 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 1600 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 3200 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 6400 mM TEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition is substantially free of additional components having a pKa of about 7.0 to about 8.0. In embodiments, the composition is free of Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, POPSO, HEPPSO, and PIPES. In embodiments, the composition further comprises an ECL labeling component.In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0118] In embodiments, the present disclosure provides a composition comprising TEA, an ionic component, and optionally one or both of an ECL label component and a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and optionally the composition is substantially free of additional pH buffering components. In embodiments, the composition comprises about 1000 mM to about 6500 mM TEA and about 500 mM to about 2000 mM of the ionic component. In embodiments, the surfactant comprises alkyl ether-PEG. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition consists essentially of or consists of the recited components.

[0119] In embodiments, the present disclosure provides a composition comprising TEA, an ionic component, and one or both of an ECL label component and a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and optionally, the composition is substantially free of additional pH buffering components. In embodiments, the composition comprises about 1000 mM to about 6500 mM TEA and about 500 mM to about 2000 mM of the ionic component. In embodiments, the surfactant comprises alkyl ether-PEG. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition consists essentially of or consists of the recited components.

[0120] In embodiments, the present disclosure provides a composition comprising TEA, an ionic component, and optionally one or both of an ECL label component and a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and the composition is substantially free of additional pH buffering components. In embodiments, the composition comprises about 1000 mM to about 6500 mM TEA and about 500 mM to about 2000 mM of the ionic component. In embodiments, the surfactant comprises alkyl ether-PEG. In embodiments, the composition consists essentially of or consists of the recited components.

[0121] In embodiments, the present disclosure provides a composition comprising TEA, an ionic component, a surfactant, and an ECL-labeled component, wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the present disclosure provides a composition comprising TEA, an ionic component, and a surfactant, wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the present disclosure provides a composition comprising TEA, an ionic component, a surfactant, an ECL-labeled component, and a surfactant, wherein the composition has a pH of about 7.0 to about 8.0. In embodiments, the composition comprises about 1000 mM to about 6500 mM TEA and about 500 mM to about 2000 mM of the ionic component. In embodiments, the surfactant comprises alkyl ether-PEG. In embodiments, the composition is substantially free of additional pH buffering components. In embodiments, the composition consists essentially of or consists of the recited components.

[0122] In embodiments, the compositions provided herein are in dry form. In embodiments, the compositions provided herein are in dry powder form. In embodiments, the compositions provided herein are lyophilized powders. Throughout this disclosure, when a composition comprises a particular concentration of its recited components (e.g., about 1000 mM to about 6500 mM TEA, about 500 mM to about 2000 mM ionic components, and / or about 0.1 mM to about 10 mM surfactant), and / or a particular pH of its recited components (e.g., a pH of about 7.0 to about 8.0), it will be understood by those skilled in the art that the recited concentrations and pH of the components of the composition refer to the composition in liquid form, e.g., a dry composition reconstituted with a liquid diluent (e.g., water or an aqueous assay buffer). In embodiments, the composition is in dry form and, when reconstituted with a liquid diluent, comprises the recited components at the recited concentrations. In embodiments, the composition is in dry form and, when constituted with a liquid diluent, comprises the recited pH.

[0123] Alkyldiethanolamine / zwitterionic tertiary amine compositions In embodiments, the present disclosure provides a composition comprising about 50 mM to about 250 mM tBDEA, about 500 mM to about 1500 mM ionic components, and about 0.1 mM to about 10 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0124] In embodiments, the present disclosure provides a composition comprising about 50 mM to about 250 mM MDEA, about 500 mM to about 1500 mM ionic components, and about 0.1 mM to about 10 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0125] In embodiments, the present disclosure provides a composition comprising about 50 mM to about 250 mM DEA-PS, about 500 mM to about 1500 mM ionic components, and about 0.1 mM to about 10 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR™ P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0126] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0127] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0128] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR™ P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0129] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0130] In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0131] In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0132] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM to about 5 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0133] In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM to about 5 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0134] In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 700 mM to about 900 mM of an ionic component, and about 1 mM to about 5 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0135] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 850 mM NaCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0136] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 850 mM NaCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, and the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0137] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 850 mM NaCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0138] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 850 mM KCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0139] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 850 mM KCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0140] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 850 mM KCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0141] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 850 mM LiCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0142] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 850 mM LiCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0143] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 850 mM LiCl, and about 1 mM to about 5 mM of a surfactant, the composition having a pH of about 7.0 to about 8.0, the surfactant being selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0144] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 700 mM to about 900 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and the surfactant is 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100). In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 700 mM to about 900 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and the surfactant is 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100). In an embodiment, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 700 mM to about 900 mM of an ionic component, and about 1 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, and the surfactant is 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100). In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In an embodiment, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL label component. In an embodiment, the ECL label component is a detection reagent comprising an ECL label.

[0145] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 700 mM to about 900 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate) tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 700 mM to about 900 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate) tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 700 mM to about 900 mM ionic components, and about 1 mM surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0146] In one embodiment, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is PEG(18) tridecyl ether. In another embodiment, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 700 mM to about 900 mM of an ionic component, and about 1 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is PEG(18) tridecyl ether. In an embodiment, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 700 mM to about 900 mM of an ionic component, and about 1 mM of a surfactant, wherein the composition has a pH of about 7.0 to about 8.0, the ionic component is NaCl, KCl, or LiCl, and the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In an embodiment, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL label component. In an embodiment, the ECL label component is a detection reagent comprising an ECL label.

[0147] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.5, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18(PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0148] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM tBDEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.8, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0149] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.5, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0150] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM MDEA, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.8, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0151] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.5, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0152] In embodiments, the present disclosure provides a composition comprising about 100 mM to about 200 mM DEA-PS, about 700 mM to about 900 mM ionic components, and about 1 mM to about 5 mM surfactant, wherein the composition has a pH of about 7.8, the ionic components are NaCl, KCl, or LiCl, and the surfactant is selected from the group consisting of 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO -72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In an embodiment, the surfactant is PEG(18) tridecyl ether. In an embodiment, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In an embodiment, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In an embodiment, the composition further comprises an ECL labeling component. In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0153] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM NaCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In embodiments, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component.In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0154] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM KCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In embodiments, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component.In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0155] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM LiCl, and about 1 mM 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol (TRITON™ X-100), wherein the composition has a pH of about 7.8. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In embodiments, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component.In embodiments, the ECL labeled component is a detection reagent that includes an ECL label.

[0156] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM NaCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM NaCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0157] In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM NaCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM NaCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0158] In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM NaCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM NaCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0159] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM KCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM KCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0160] In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM KCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM KCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0161] In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM KCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM KCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0162] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM LiCl, and about 1 mM surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate block ethoxylate) tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM LiCl, and about 1 mM surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0163] In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM LiCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM LiCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0164] In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM LiCl, and about a surfactant, wherein the composition has a pH of about 7.5, and the surfactant is selected from the group consisting of Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM LiCl, and about 1 surfactant, the composition having a pH of about 7.8, and the surfactant being Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, alkyl ether-polyethylene glycol (PEG), or a combination thereof. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffer component. In embodiments, the pH buffer component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0165] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM NaCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In embodiments, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0166] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM KCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In embodiments, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0167] In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM tBDEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM MDEA, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.5. In embodiments, the present disclosure provides a composition comprising about 150 mM DEA-PS, about 850 mM LiCl, and about 1 mM PEG(18) tridecyl ether, wherein the composition has a pH of about 7.8. In embodiments, the composition further comprises about 100 mM to about 200 mM of a pH buffering component. In embodiments, the pH buffering component is Tris, phosphate, HEPES, glycylglycine, borate, acetate, citrate, or a combination thereof. In embodiments, the composition further comprises an ECL label component. In embodiments, the ECL label component is a detection reagent comprising an ECL label.

[0168] In embodiments, the present disclosure provides a composition comprising an ECL coreactant, an ionic component, and a surfactant. In embodiments, the ECL coreactant is tributylamine (TBA), (dibutyl)aminoethanol (DBAE), (diethyl)aminoethanol (DEAE), triethanolamine (TEA), butyldiethanolamine (BDEA), propyldiethanolamine (PDEA), ethyldiethanolamine (EDEA), methyldiethanolamine (MDEA), tert-butyldiethanolamine (tBDEA), dibutylamine (DBA), butylethanolamine (BEA), diethanolamine (DEA), dibutylamine propylsulfonate (DBA-PS), dibutylamine butylsulfonate (DBA-BS), butylethanolamine propylsulfonate (BEA-PS), butylethanolamine butylsulfonate (BEA-BS), diethanolamine propylsulfonate (also known as 3-[bis-(2-hydroxyethyl)-amino]-propane-1-sulfonic acid, DEA-PS), diethanolamine butylsulfonate (DEA-BS), or a combination thereof. In embodiments, the composition has a pH of about 7.0 to about 8.0. In embodiments, the composition further comprises a pH buffering component. Suitable ionic components (e.g., NaCl, KCl, and LiCl), detergents (e.g., TRITON X-100 or a mild detergent described herein), pH buffering components (e.g., Tris or phosphate), and their concentrations in the composition are provided herein. In embodiments, the composition further comprises an ECL labeling component. In embodiments, the ECL labeling component is a detection reagent comprising an ECL label.

[0169] method In embodiments, the present disclosure provides a method for generating electrochemiluminescence (ECL), the method comprising: (a) contacting an electrode with an ECL coreactant composition provided herein; (b) applying a voltage to the electrode; and (c) generating ECL. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the present disclosure provides a method for generating electrochemiluminescence (ECL), the method comprising: (a) contacting an electrode with a TEA composition comprising TEA, an ionic component, and optionally a surfactant; (b) applying a voltage to the electrode; and (c) generating ECL. In embodiments, the method further comprises detecting the generated ECL. In an embodiment, the method further comprises measuring the ECL produced. In an embodiment, the electrode is on a surface.

[0170] In embodiments, the present disclosure provides a method of generating electrochemiluminescence (ECL), comprising: (a) contacting an electrode with (i) an ECL coreactant composition provided herein and (ii) an ECL label; (b) applying a voltage to the electrode; and (c) generating ECL. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the present disclosure provides a method for generating electrochemiluminescence (ECL), comprising: (a) contacting an electrode with (i) a TEA composition comprising TEA, an ionic component, and optionally a surfactant, and (ii) an ECL label; (b) applying a voltage to the electrode; and (c) generating ECL. In embodiments, the method further comprises detecting the generated ECL. In embodiments, the method further comprises measuring the generated ECL, thereby quantifying the amount of ECL label. In embodiments, the electrode is present on a surface.

[0171] In embodiments, the present disclosure provides a method for quantifying the amount of ECL label in a sample, the method comprising: (a) contacting an electrode with (i) an ECL coreactant composition provided herein or a TEA composition provided herein, and (ii) the sample containing the ECL label; (b) applying a voltage to the electrode; (c) generating ECL; (d) measuring the ECL; and (e) quantifying the amount of ECL label from the measured ECL. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant.

[0172] In embodiments, ECL is generated from a reaction between an ECL coreactant (e.g., TEA, tBDEA, MDEA, and / or DEA-PS) and an ECL label in the compositions herein. In embodiments, the ECL label is present on an ECL label component. In embodiments, the ECL label is present in a sample. In embodiments, the sample comprises an ECL label component. In embodiments, the ECL label component comprises a detection reagent. In embodiments, the sample comprises a binding partner of the ECL label component. In embodiments, the ECL label component comprises a binding partner of the detection reagent. In embodiments, the detection reagent is part of a binding complex comprising the detection reagent, the analyte, and a capture reagent, and the capture reagent comprises a binding partner for a binding reagent immobilized on a surface. In embodiments, the ECL label component is an oligonucleotide probe complementary to an extension primer attached to a detection reagent (e.g., a detection antibody) that binds to a target analyte, such as a peptide or protein. Detection reagents and their binding partners are further described herein. In embodiments, the ECL-labeled component is present in a binding complex, and the method further comprises detecting the binding complex by detecting the ECL produced. In embodiments, the method comprises contacting an electrode with a sample containing a binding partner of the ECL-labeled component, wherein the ECL-labeled component and the binding partner form a binding complex, and the method further comprises detecting the binding complex by detecting the ECL produced. In embodiments, the method comprises measuring the ECL produced, thereby quantifying the amount of ECL-labeled component and / or binding complex.

[0173] In embodiments, each of the sample, the ECL coreactant composition or TEA composition provided herein, and the ECL-labeled component is dry. In embodiments, each of the sample, the ECL coreactant composition or TEA composition provided herein, and the ECL-labeled component is liquid. In embodiments, one or more of the sample, the ECL coreactant composition or TEA composition provided herein, and the ECL-labeled component is dry, and the remaining component(s) are liquid. For example, the sample is liquid, and one or both of the ECL coreactant composition or TEA composition provided herein and the ECL-labeled component are dry. In embodiments including liquid and dry components, the liquid component reconstitutes the dry component. In embodiments, the method further includes contacting the electrode with a liquid diluent, thereby reconstituting the dry component(s) in the liquid. In embodiments, the dry component(s) is / are present on a surface. In embodiments, the ECL coreactant composition is dry and present on a surface. In embodiments, the TEA composition is dry and present on a surface. In embodiments, the ECL-labeled component is dry and present on a surface. Dry forms of the compositions are described herein. In embodiments, the ECL-labeled component is a detection reagent comprising an ECL label. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant.

[0174] In embodiments, the ECL-labeled component in the binding complex is a first copy of a detection reagent that includes an ECL label. In embodiments, the binding complex comprises a first copy of a detection reagent and a binding reagent immobilized on a surface. The binding reagent is further described herein. In embodiments, the method further comprises forming a binding complex. In embodiments, the binding complex is formed before or during step (a) of the method.

[0175] In embodiments, the binding complex is formed by incubating an assay mixture comprising a binding reagent, a first copy of a detection reagent, and a second copy of the detection reagent comprising an ECL label under conditions in which the binding complex forms on the surface and the second copy of the detection reagent remains in solution. In embodiments, the ECL coreactant composition comprises TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant.

[0176] In embodiments, the binding complex is formed by incubating an assay mixture comprising a binding reagent, a first copy of a detection reagent, a second copy of the detection reagent comprising an ECL label, and an ECL coreactant composition or a TEA composition provided herein under conditions in which the binding complex forms on the surface and the second copy of the detection reagent remains in solution. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the composition comprises TEA. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant.

[0177] In embodiments, the binding complex is formed by combining a sample with a first copy of a detection reagent, a second copy of a detection reagent comprising an ECL label, and an ECL coreactant composition or a TEA composition provided herein, thereby forming an assay mixture, and contacting the assay mixture with the binding reagent under conditions such that the binding complex forms on the surface and the second detection reagent remains in solution. In embodiments, the ECL coreactant composition comprises TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant.

[0178] In embodiments, the binding complex further comprises an analyte. The analyte is further described herein. In embodiments, the binding reagent and the detection reagent each specifically bind to the analyte. In embodiments, the method comprises detecting the analyte by detecting the ECL produced. In embodiments, the method comprises measuring the ECL produced, thereby quantifying the amount of analyte.

[0179] In embodiments, the ECL label comprises an electrochemiluminescent organometallic complex. In embodiments, the electrochemiluminescent organometallic complex comprises ruthenium, osmium, iridium, rhenium, and / or a lanthanide metal. In embodiments, the ECL label comprises ruthenium. In embodiments, the ECL label comprises ruthenium(II) tris-bipyridine. In embodiments, the electrochemiluminescent organometallic complex comprises a substituted or unsubstituted bipyridine or a substituted or unsubstituted phenanthroline. In embodiments, the ECL label comprises a substituted bipyridine. In embodiments, the ECL label comprises an organometallic complex comprising at least one substituted bipyridine ligand, wherein the substituted bipyridine ligand comprises at least one sulfonate group. In embodiments, the ECL label comprises an organometallic complex comprising at least two substituted bipyridine ligands, wherein each substituted bipyridine ligand comprises at least one sulfonate group. In embodiments, the substituted bipyridine ligand comprising at least one sulfonate group is a compound of Formula I. In embodiments, the ECL label comprises a compound of formula II.

[0180] In embodiments, the compositions herein are used in ECL-based binding assays, e.g., to detect and / or quantitate an analyte of interest and / or a binding complex comprising the analyte. In embodiments, the binding complex is formed on a surface, e.g., an electrode, and the binding complex comprises an ECL label capable of generating ECL when contacted with an ECL coreactant described herein. Binding assay formats include, but are not limited to, the following: (1) direct binding assays, in which the analyte of interest is labeled with an ECL label, a binding reagent that is the binding partner of the analyte is immobilized on a surface, and a binding complex is formed by direct binding between the binding reagent and the labeled analyte; (2) sandwich binding assays, in which both the immobilized binding reagent and the ECL-labeled detection reagent are binding partners of the analyte, and the analyte binds to the two binding partners to form a binding complex; and (3) competitive binding assays, in which the immobilized binding reagent is the binding partner of the analyte and the labeled detection reagent is a competitor (e.g., the analyte or a structural analog of the analyte) that competes with the immobilized binding reagent for binding to the analyte, or the labeled detection reagent is the binding partner of the analyte and the immobilized binding reagent is a competitor that competes with the detection reagent for binding to the analyte. In competitive binding assays, the amount of the labeled binding complex formed by direct binding between the immobilized binding reagent and the labeled detection reagent decreases as the amount of analyte increases. Binding assays are further described in, for example, WO2014 / 165061, WO2014 / 160192, WO2015 / 175856, US9,618,510, US10,114,015, US10,408,823, US2017 / 0168047, and US2019 / 0011441, each of which is incorporated by reference herein in its entirety.

[0181] In embodiments, the present disclosure provides a method for detecting a binding complex, the method comprising: (a) contacting a liquid sample with a surface comprising an ECL coreactant or TEA composition provided herein, wherein the liquid sample comprises an ECL-labeled component or a binding partner of the ECL-labeled component, and the method further comprises contacting the surface with the ECL-labeled component, thereby forming a binding complex on the surface comprising the ECL-labeled component; (b) applying a voltage to the surface to generate ECL; and (c) detecting the generated ECL, thereby detecting the binding complex. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant. In embodiments, the surface comprises an electrode. In embodiments, the ECL-labeled component comprises a detection reagent comprising an ECL label. In embodiments, the ECL-labeled component comprises a detection reagent comprising an ECL label, and the binding complex comprises the binding reagent and the detection reagent. In embodiments, the ECL-labeled component comprises a binding partner of the detection reagent, and the binding partner comprises an ECL label. In embodiments, the ECL-labeled component comprises a binding partner of the detection reagent, and the binding complex comprises the binding reagent, the detection reagent, and the binding partner. The detection reagent and the binding partner are further described herein. In embodiments, the detection reagent and the ECL-labeled component comprise complementary oligonucleotides. In embodiments, the binding complex further comprises an analyte. In embodiments, the binding reagent and the detection reagent each specifically bind to the analyte.

[0182] In embodiments, the present disclosure provides a method for detecting a binding complex, the method comprising: (a) contacting a liquid sample with a surface comprising an ECL-labeled component and an ECL coreactant composition or a TEA composition provided herein, the liquid sample comprising a binding partner of the ECL-labeled component, thereby forming a binding complex on the surface comprising the ECL-labeled component; (b) applying a voltage to the surface to generate ECL; and (c) detecting the generated ECL, thereby detecting the binding complex. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant. In embodiments, the surface comprises an electrode. In embodiments, the ECL-labeled component comprises a detection reagent comprising an ECL label. In embodiments, the ECL-labeled component comprises a detection reagent comprising an ECL label, and the binding complex comprises the binding reagent and the detection reagent. In embodiments, the ECL-labeled component comprises a binding partner of the detection reagent, and the binding partner comprises an ECL label. In embodiments, the ECL-labeled component comprises a binding partner of the detection reagent, and the binding complex comprises the binding reagent, the detection reagent, and the binding partner. The detection reagent and the binding partner are further described herein. In embodiments, the detection reagent and the ECL-labeled component comprise complementary oligonucleotides. In embodiments, the binding complex further comprises an analyte. In embodiments, the binding reagent and the detection reagent each specifically bind to the analyte.

[0183] In embodiments, the present disclosure provides a method for detecting a binding complex, the method comprising: (a) forming a binding complex on a surface, the binding complex comprising an ECL-labeled component; (b) contacting the binding complex with an ECL coreactant composition or a TEA composition provided herein; (c) applying a voltage to the surface to generate ECL; and (d) detecting the generated ECL, thereby detecting the binding complex. In embodiments, the ECL coreactant composition comprises TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant. In embodiments, the surface comprises an electrode. In embodiments, the ECL-labeled component comprises a detection reagent comprising an ECL label. In embodiments, the ECL-labeled component comprises a detection reagent comprising an ECL label, and the binding complex comprises the binding reagent and the detection reagent. In embodiments, the ECL-labeled component comprises a binding partner of the detection reagent, and the binding partner comprises an ECL label. In embodiments, the ECL-labeled component comprises a binding partner of the detection reagent, and the binding complex comprises the binding reagent, the detection reagent, and the binding partner. The detection reagent and the binding partner are further described herein. In embodiments, the detection reagent and the ECL-labeled component comprise complementary oligonucleotides. In embodiments, the binding complex further comprises an analyte. In embodiments, the binding reagent and the detection reagent each specifically bind to the analyte.

[0184] In embodiments, the present disclosure provides a method for detecting a binding complex, the method comprising: (a) forming a binding complex on a surface, the surface including an electrode, the binding complex including a binding reagent immobilized on the surface and a detection reagent including an electrochemiluminescence (ECL) label; (b) contacting the binding complex with an ECL coreactant composition or a TEA composition provided herein; (c) applying a voltage to the surface to generate ECL; and (d) detecting the generated ECL, thereby detecting the binding complex. In embodiments, the binding complex further includes an analyte, and the binding reagent and detection reagent each specifically bind to the analyte. In embodiments, the ECL coreactant composition includes TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant. In embodiments, the binding complex further comprises an analyte. In embodiments, the binding reagent and the detection reagent each specifically bind to the analyte.

[0185] In embodiments, the present disclosure provides a method for detecting an analyte of interest in a sample, the method comprising: (a) contacting the sample with (i) a surface comprising a binding reagent, the binding reagent specifically binding to the analyte, and (ii) a detection reagent specifically binding to the analyte, the detection reagent comprising an electrochemiluminescence (ECL) label, thereby forming a binding complex on the surface comprising the binding reagent, the analyte, and the detection reagent; (b) contacting the binding complex on the surface with an ECL coreactant composition or a TEA composition provided herein; (c) applying a voltage to the surface to generate ECL; and (d) detecting the generated ECL. In embodiments, the ECL coreactant composition comprises TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant. In embodiments, the surface comprises an electrode. In embodiments, the analyte of interest is an oligonucleotide, and the detection reagent that specifically binds to the analyte is an oligonucleotide probe comprising an ECL label and a quenching moiety that quenches the ECL signal at least when the ECL-labeled oligonucleotide probe is not hybridized to a complementary oligonucleotide. In embodiments, the ECL-labeled oligonucleotide probe comprises a stem-loop or hairpin structure, an ECL label, and a quenching moiety that is adjacent to the ECL label and quenches the ECL label when the ECL-labeled oligonucleotide probe is in the stem-loop or hairpin configuration, but does not quench the ECL label when the stem-loop or hairpin structure is in an open configuration (e.g., as shown in Figures 14 and 20). In an embodiment, the ECL-labeled oligonucleotide probe having a stem-loop or hairpin structure is an ECL-labeled molecular beacon probe.In embodiments, the ECL-labeled oligonucleotide probe comprises an ECL label and a quencher, which are sufficiently close to each other on the probe when the probe is in a linear configuration (e.g., not a stem-loop or hairpin configuration) such that in the linear configuration, the quenching moiety quenches the ECL signal regardless of whether the probe is hybridized to a complementary oligonucleotide (e.g., as shown in Figure 21).

[0186] In embodiments, the present disclosure provides a method for detecting an analyte of interest in a sample, the method comprising contacting the sample with (i) a surface comprising a binding reagent, the binding reagent specifically binding to a binding complex comprising the analyte (e.g., a peptide), (ii) a capture reagent (e.g., an antibody) that specifically binds to the analyte, the capture reagent further comprising a binding partner for the binding reagent (e.g., biotin / streptavidin), (iii) a detection reagent that specifically binds to the analyte, the detection reagent comprising an oligonucleotide primer (e.g., an oligonucleotide-labeled antibody), (iv) a template oligonucleotide, and (v) an ECL-labeled oligonucleotide probe. In embodiments, the capture reagent and detection reagent bind to the analyte, the primer binds to the template oligonucleotide, the primer is extended by amplification of the template oligonucleotide, and the ECL-labeled oligonucleotide probe binds to the extended primer oligonucleotide (e.g., as shown in Figure 20). In embodiments, the binding complex comprises the binding partner, the analyte, and the detection reagent comprising the extended oligonucleotide primer. A surface is contacted with an ECL coreactant composition or a TEA composition provided herein, a voltage is applied to the surface to generate ECL, and the generated ECL is detected, thereby detecting the analyte. In embodiments, the ECL coreactant composition includes TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA. In embodiments, the TEA composition includes TEA, an ionic component, and optionally a surfactant. In embodiments, the surface includes an electrode. In embodiments, the ECL-labeled oligonucleotide probe is a molecular beacon probe.

[0187] As discussed herein, the compositions provided herein can be used in ECL-based assays that do not require a washing step. A "washing step," as used in the context of an ECL-based assay performed on a surface, refers to the addition of a wash buffer to the surface to remove undesired components from the assay reaction mixture, such as excess, nonspecifically bound or unbound reagents (e.g., detection reagents and / or ECL labels) and / or unbound or nonspecifically bound components of the sample. In one example, a biological sample can contain the analyte of interest and various other biological materials that are not of interest and do not specifically bind to the binding reagent, and a washing step can remove such components from the reaction mixture. In embodiments, the composition includes TEA. In embodiments, the composition includes TEA, an ionic component, and, optionally, a surfactant. In a "washing" assay, a washing step is typically used to remove unbound ECL label before detecting the ECL label on the surface. A washing step may be eliminated if the detection method can effectively distinguish between surface-bound ECL label (e.g., as part of a binding complex to be detected) and unbound "free" ECL label in solution. "No-wash" assay formats, in which the washing step is eliminated, are often advantageous because washing steps can be difficult or cumbersome to perform in many situations. However, no-wash assay formats are typically difficult to develop due to high background ECL signals resulting from incomplete discrimination between free and bound ECL labels present in the reaction mixture. Even in assays that use washing steps, good discrimination between bound and free ECL labels is advantageous because it provides tolerance for low levels of free label contamination, which may be associated with poor washing, thereby providing greater robustness against washing inefficiencies or variations in washing quality.

[0188] As discussed herein, the compositions herein surprisingly distinguish between free and bound ECL labels in ECL-based assays performed on solid surfaces (e.g., solid electrode surfaces). In embodiments, the compositions herein increase the ratio of ECL signal from bound label to ECL signal from free label. Thus, the compositions herein provide improved assay performance, particularly when measuring low-affinity interactions, which require the presence of high concentrations of ECL label in the reaction but are also expected to suffer significant signal loss due to dissociation of the binding complex during washing steps. In embodiments, the compositions comprise TEA. In embodiments, the compositions comprise TEA, an ionic component, and optionally a surfactant.

[0189] Without being bound by theory, it is believed that the compositions and ECL coreactants (e.g., TEA) herein reduce the distance from the solid electrode surface at which ECL is generated from the ECL label. This increases the signal of the bound label (held close to the electrode) compared to the free label (distributed throughout the solution above the electrode). The increase in signal from the bound label can also be characterized in terms of the "effective excitation length," which is the maximum distance over which the free ECL label can be excited. The "effective excitation length" is affected by: (1) the ability of short-distance intermediates involved in ECL generation (e.g., oxidation products of the ECL coreactant) to diffuse away from the electrode before being depleted in side reactions (a function of the lifetime and diffusion constant of these intermediates), and (2) the rate at which free label or unbound reagent diffuses into a region close enough to the electrode to participate in reactions with these reactive intermediates (a function of the diffusion constant of the unbound ECL label or labeling reagent). In methods using the compositions herein, the effective excitation length is reduced by more than 2-fold, more than 3-fold, more than 4-fold, more than 5-fold, more than 9-fold, more than 7-fold, more than 8-fold, more than 9-fold, or more than 10-fold compared to a composition comprising TPA. In embodiments, the composition comprises TEA. In embodiments, the composition comprises TEA, an ionic component, and optionally a surfactant.

[0190] In embodiments, the methods herein do not include a washing step. In embodiments in which the method detects a binding complex, the method does not include a washing step before, during, or after forming the binding complex on the surface. In embodiments in which the method detects an analyte of interest in a sample, the method does not include a washing step before, during, or after contacting the sample with (i) a surface comprising a binding reagent, where the binding reagent specifically binds to the analyte, and (ii) a detection reagent that specifically binds to the analyte. In embodiments, the method does not include a washing step before, during, or after contacting the binding complex with a composition. In embodiments, the method does not include a washing step before, during, or after applying a voltage to the surface to generate ECL. In embodiments, the method does not include a washing step before or during detecting the generated ECL. In embodiments, the composition includes TEA. In embodiments, the composition includes TEA, an ionic component, and optionally a surfactant.

[0191] In embodiments, the methods herein include a washing step. In embodiments in which the method detects a binding complex, the method includes a washing step before, during, or after forming the binding complex on the surface. In embodiments in which the method detects an analyte of interest in a sample, the method includes a washing step before, during, or after contacting the sample with (i) a surface comprising a binding reagent, where the binding reagent specifically binds to the analyte, and (ii) a detection reagent that specifically binds to the analyte. In embodiments, the method includes a washing step before, during, or after contacting the binding complex with a composition. In embodiments, the method includes a washing step before, during, or after applying a voltage to the surface to generate ECL. In embodiments, the method includes a washing step before or during detecting the generated ECL. In embodiments, the composition includes TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the composition includes TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA.

[0192] In embodiments, the present disclosure provides a method for detecting a binding complex, the method comprising: (a) forming an assay mixture by combining a sample with (i) an ECL coreactant composition or TEA composition provided herein and (ii) a detection mixture comprising at least two copies of a detection reagent, each copy of the detection reagent comprising an ECL label; (b) contacting the assay mixture with a binding reagent immobilized on a surface, optionally comprising an electrode, under conditions such that (I) a binding complex is formed on the surface, the binding complex comprising the binding reagent and a first copy of the detection reagent, and (II) a second copy of the detection reagent remains in solution; (c) applying a voltage to the surface to generate ECL; and (d) detecting the generated ECL, thereby detecting the binding complex. In embodiments, the surface comprises an electrode. In embodiments, the second copy of the detection reagent is not removed prior to any of steps (b) through (d). In embodiments, the second copy of the detection reagent is not removed prior to step (b). In embodiments, the ECL coreactant composition includes TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition includes TEA. In embodiments, the ECL coreactant composition includes TEA, BDEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the TEA composition includes TEA, an ionic component, and optionally a surfactant.

[0193] In embodiments, the present disclosure provides a method for detecting a binding complex, the method comprising: (a) incubating an assay mixture comprising: (i) a binding reagent immobilized on a surface, the surface optionally comprising an electrode; and (ii) a detection mixture comprising at least two copies of a detection reagent, each copy of the detection reagent comprising an electrochemiluminescence (ECL) label; (i) under conditions such that a binding complex is formed on the surface, the binding complex comprising the binding reagent and a first copy of the detection reagent, and (ii) a second copy of the detection reagent remains in solution; (b) contacting the binding complex with an ECL coreactant composition or a TEA composition provided herein; (c) applying a voltage to the surface to generate ECL; and (d) detecting the generated ECL, thereby detecting the binding complex. In embodiments, the surface comprises an electrode. In embodiments, the method further comprises washing the surface prior to any of steps (b)-(d), thereby removing the second copy of the detection reagent. In embodiments, the second copy of the detection reagent is not removed prior to any of steps (b)-(d). In embodiments, the second copy of the detection reagent is not removed prior to step (b). In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant.

[0194] In embodiments, the present disclosure provides a method for detecting a binding complex, the method comprising: (a) incubating an assay mixture comprising: (i) a binding reagent immobilized on a surface, the surface optionally comprising an electrode; (ii) a detection mixture comprising at least two copies of a detection reagent, each copy of the detection reagent comprising an electrochemiluminescence (ECL) label; and (iii) an ECL coreactant composition or a TEA composition provided herein, under conditions such that a binding complex forms on the surface, the binding complex comprising the binding reagent and a first copy of the detection reagent, and (ii) a second copy of the detection reagent remains in solution; (b) applying a voltage to the surface to generate ECL; and (c) detecting the generated ECL, thereby detecting the binding complex. In embodiments, the surface comprises an electrode. In embodiments, the method further comprises washing the surface prior to either step (b) or (c), thereby removing the second copy of the detection reagent. In embodiments, the second copy of the detection reagent is not removed prior to either step (b) or (d). In embodiments, the second copy of the detection reagent is not removed prior to step (b). In embodiments, the ECL coreactant composition comprises TEA, tBDEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, tBDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA, BDEA, MDEA, DEA-PS, or a combination thereof. In embodiments, the ECL coreactant composition comprises TEA. In embodiments, the TEA composition comprises TEA, an ionic component, and optionally a surfactant.

[0195] In embodiments, the binding complex further comprises an analyte, and the first copy of the binding reagent and the detection reagent each specifically bind to the analyte.

[0196] In embodiments, at least two copies of the binding reagent are immobilized on a surface, and a first copy of the binding reagent is complexed with a first copy of the detection reagent, and a second copy of the binding reagent is bound to the competitor such that it is not complexed with the second copy of the detection reagent. In embodiments, at least two copies of the binding reagent are immobilized on a surface, and a first copy of the binding reagent is complexed with a first copy of the detection reagent, and a second copy of the detection reagent is bound to the competitor such that it is not complexed with the second copy of the detection reagent. Competitors and competitive assay formats are further described herein.

[0197] In embodiments, the binding reagent binds to a first copy of the detection reagent to form a binding complex.

[0198] In embodiments, the binding reagent comprises an antibody or antigen-binding fragment thereof, an antigen, a ligand, a receptor, an oligonucleotide, a hapten, an epitope, a mimotope, or an aptamer. In embodiments, the binding reagent is an antibody or variant thereof, including its antigen / epitope-binding portion, an antibody fragment or derivative, an antibody analog, an engineered antibody, or a substance that binds to an antigen in a manner similar to an antibody. In embodiments, the binding reagent comprises at least one heavy or light chain complementarity-determining region (CDR) of an antibody. In embodiments, the binding reagent comprises at least two CDRs from one or more antibodies. In embodiments, the binding reagent is an antibody or antigen-binding fragment thereof. In embodiments, the binding reagent specifically binds to an analyte. As used herein, "specifically binds" means that the reagent (e.g., the binding reagent) preferentially binds to its binding partner (e.g., the epitope of the analyte) compared to random, unrelated substances. In embodiments, the binding reagent is an antibody or antigen-binding fragment thereof, comprising a binding domain that specifically binds to an epitope of the analyte.

[0199] In embodiments, the binding reagent is immobilized on a surface. In embodiments, the binding reagent is directly immobilized on a surface. In embodiments, the binding reagent is indirectly immobilized on a surface via a secondary binding partner on the binding reagent and the surface. Exemplary secondary binding partners include, but are not limited to, complementary oligonucleotides, receptor-ligand pairs, antigen-antibody pairs, hapten-antibody pairs, epitope-antibody pairs, mimotope-antibody pairs, aptamer-target molecule pairs, hybridization partners, intercalator-target molecule pairs, and mutually reactive moieties (e.g., thiol and maleimide or iodoacetamide, aldehyde and hydrazide, or azide and alkyne or cycloalkyne).

[0200] In embodiments, the detection reagent comprises an antibody or antigen-detecting fragment thereof, an antigen, a ligand, a receptor, an oligonucleotide, a hapten, an epitope, a mimotope, or an aptamer. In embodiments, the detection reagent is an antibody or variant thereof, including its antigen / epitope-detecting portion, an antibody fragment or derivative, an antibody analog, an engineered antibody, or a substance that binds to the antigen in a manner similar to an antibody. In embodiments, the detection reagent comprises at least one heavy or light chain complementarity-determining region (CDR) of an antibody. In embodiments, the detection reagent comprises at least two CDRs from one or more antibodies. In embodiments, the detection reagent is an antibody or antigen-detecting fragment thereof. In embodiments, the detection reagent specifically binds to the analyte. In embodiments, the detection reagent is an antibody or antigen-binding fragment thereof that includes a binding domain that specifically binds to an epitope of the analyte. In embodiments, the detection reagent binds to a different epitope of the analyte than the binding reagent. In embodiments, both the binding reagent and the detection reagent are antibodies or antigen-binding fragments thereof.

[0201] In embodiments, the detection reagent comprises an ECL label. In embodiments, the ECL label comprises an electrochemiluminescent organometallic complex. In embodiments, the organometallic complex comprises ruthenium, osmium, iridium, rhenium, and / or a lanthanide metal. In embodiments, the organometallic complex comprises a substituted or unsubstituted bipyridine or a substituted or unsubstituted phenanthroline. In embodiments, the ECL label comprises ruthenium. In embodiments, the ECL label comprises ruthenium(II) tris-bipyridine. In embodiments, the ECL label comprises a substituted bipyridine. In embodiments, the ECL label comprises an organometallic complex comprising at least one substituted bipyridine ligand, wherein the substituted bipyridine ligand comprises at least one sulfonate group. In embodiments, the ECL label comprises an organometallic complex comprising at least two substituted bipyridine ligands, wherein each substituted bipyridine ligand comprises at least one sulfonate group. In embodiments, the substituted bipyridine ligand comprising at least one sulfonate group is a compound of Formula I. In embodiments, the ECL label comprises a compound of Formula II. Exemplary ECL labels are provided in US 5,714,089, US 6,136,268, US 6,316,607, US 6,468,741, US 6,479,233, US 6,808,939, and US 9,499,573, each of which is incorporated herein by reference in its entirety.

[0202] In embodiments, the binding reagent and / or detection reagent directly bind to the analyte. For example, the binding reagent and detection reagent are, respectively, antibodies or antigen-binding fragments thereof that specifically bind to epitopes on the analyte. In embodiments, the binding reagent and / or detection reagent indirectly bind to the analyte via a secondary interaction. In embodiments, the analyte is linked to a binding partner of the binding reagent and / or detection reagent. For example, the binding reagent and / or detection reagent includes streptavidin, and the analyte is linked to biotin. Further examples of binding partners that can be recognized by secondary interactions include, for example, avidin-biotin, streptavidin-biotin, antibody-hapten, antibody-epitope tag, nucleic acid-complementary nucleic acid, aptamer-aptamer target, and receptor-ligand.

[0203] In embodiments, the surface comprises a multi-well plate. In embodiments, the surface comprises particles. In embodiments, the surface comprises an assay cartridge. In embodiments, the surface comprises the surface of a slide, chip, well, assay cell or flow cell, tube, channel, bead, or microparticle. In embodiments, the surface comprises particles, and the method further comprises collecting the particles on an additional surface and applying a voltage to the particles on the additional surface. In embodiments, the particles are beads (such as magnetic beads), and the method further comprises collecting the bead(s) on a magnetized plate, the plate comprising an electrode, and applying a voltage to the plate. In embodiments, the surface and / or additional surface comprises an electrode. In embodiments, the electrode is a carbon electrode, a platinum electrode, a gold electrode, or a silver electrode. In embodiments, the electrode is a carbon ink electrode. In embodiments, the substrate surface comprises an electrode. In embodiments, the substrate comprises an electrode layer coated thereon.

[0204] In embodiments, the method includes measuring the amount of an analyte or binding complex of interest in a sample. Approaches using measured amounts of ECL signal to determine the amount and / or concentration of an ECL label (or analyte or binding complex) in an ECL-based binding assay are known to those of skill in the art and include, for example, using calibration standards and / or calibration curves to establish a relationship between ECL signal and the amount and / or concentration of the ECL label and / or analyte. Calibration can be performed at different times, for example, during method development, during qualification of a particular lot of assay material, and / or at the time of assay measurement. Calibration may also be performed using calculations based on the known physical and chemical behavior of the assay components and measurement equipment.

[0205] The methods herein can be used to test a variety of samples that may contain the analyte of interest. In embodiments, the sample is a biological sample. In embodiments, the sample may be a cell (live or dead), an immortalized cell, a cell-derived product, a cell fragment, a cell fraction, a cell lysate (fractionated or unfractionated), a eukaryotic cell, a prokaryotic cell, an organelle, a cell nucleus and fractions thereof, a cell membrane, a hybridoma, a cell culture supernatant (e.g., a supernatant from an antibody-producing organism such as a hybridoma), a cytoskeleton, a protein complex, a structural biological component, a skeletal component such as ligaments and tendons, hair, fur, feathers, a hair fraction, skin, dermis, endothelium, a mammalian fluid, a secretion, an excretion, whole blood, plasma, serum, sputum, tears, lymph, synovial fluid, pleural effusion, urine, sweat, cerebrospinal fluid, peritoneal fluid, milk, feces, bronchial lavage, saliva, amniotic fluid, nasal secretions, vaginal secretions, a scraping biopsy, sperm, semen / seminal fluid, or the like. fluid, wound secretions and excretions, mucosal swabs, tissue aspirates, tissue homogenates, or extractions, purifications, or dilutions thereof. In embodiments, the sample is derived from plants, plant by-products, soil, water sources, oil, wastewater, or environmental samples. In embodiments, the sample further comprises water, an organic solvent (e.g., acetonitrile, dimethyl sulfoxide, dimethylformamide, n-methylpyrrolidone, alcohol, or a combination thereof), EDTA, heparin, citrate, or a combination thereof. The sample may be obtained from a single source as described herein or may contain a mixture from two or more sources.

[0206] Analytes that can be measured using the methods of the present disclosure include, but are not limited to, whole cells, cell surface antigens, intracellular particles (e.g., organelles or membrane fragments), exosomes, extracellular vesicles, liposomes, membrane vesicles, viruses, prions, house dust mites or fragments thereof, viroids, antibodies, antigens, haptens, fatty acids, nucleic acids (and synthetic analogs), proteins (and synthetic analogs), lipoproteins, polysaccharides, inhibitors, cofactors, haptens, cellular receptors, receptor ligands, lipopolysaccharides, glycoproteins, peptides, polypeptides, enzymes, enzyme substrates, enzyme products, second messengers, cellular metabolites, hormones, pharmacological agents, synthetic organic molecules, organometallic molecules, tranquilizers, barbiturates, alkaloids, steroids, vitamins, amino acids, sugars, lectins, recombinant or derived proteins, biotin, avidin, streptavidin, or inorganic molecules present in a sample. Activities that may be measured include, but are not limited to, activities of phosphorylases, phosphatases, esterases, transglutaminases, nucleic acid damaging activities, transferases, oxidases, reductases, dehydrogenases, glycosidases, ribosomal, protein processing enzymes (e.g., proteases, kinases, protein phosphatases, ubiquitin-protein ligases, etc.), nucleic acid processing enzymes (e.g., polymerases, nucleases, integrases, ligases, helicases, telomerases, etc.), cell receptor activation, second messenger system activation, and the like.

[0207] Whole cells may be animal, plant, or bacterial, and may be living or dead. Examples include plant pathogens such as fungi and nematodes. The term "intracellular particle" has its plain and ordinary meaning as understood herein and includes, for example, intracellular organelles, membrane particles from disrupted cells, cell wall fragments, ribosomes, multienzyme complexes, and other particles that may be derived from living organisms. Nucleic acids include, for example, chromosomal DNA, plasmid DNA, viral DNA, and recombinant DNA derived from multiple sources. Nucleic acids also include RNA, for example, messenger RNA, ribosomal RNA, and transfer RNA. Polypeptides include, for example, structural proteins such as enzymes, transport proteins, receptor proteins, and viral coat proteins. In embodiments, the polypeptide is an enzyme or an antibody. In embodiments, the polypeptide is a monoclonal antibody. Hormones include, for example, insulin and T4 thyroid hormone. Pharmacological agents include, for example, cardiac glycosides. It is within the scope of this disclosure to include synthetic substances that chemically resemble biological materials, such as synthetic polypeptides, synthetic nucleic acids, and synthetic membranes, vesicles, and liposomes. The above is not intended to be an exhaustive list of biological substances suitable for use in this disclosure, but is intended only to illustrate the broad scope of the present disclosure.

[0208] In embodiments, the methods herein are multiplexed methods capable of detecting multiple binding complexes and / or analytes. In embodiments, the multiplexed methods detect multiple binding complexes and / or analytes simultaneously. In embodiments, the multiplexed methods include repeating one or more method steps to measure multiple binding complexes and / or analytes. In embodiments, each of the method steps is performed in parallel for each binding complex and / or analyte. In embodiments in which the method detects multiple binding complexes, each binding complex comprises a different binding reagent and / or detection reagent. In embodiments in which the method detects multiple analytes, each analyte binds to a different binding reagent and / or detection reagent. In embodiments, the binding of each analyte to its corresponding binding reagent is performed in parallel by contacting the surface(s) with a sample containing multiple analytes.

[0209] In embodiments, the multiplexing method does not include a wash step. Multiplexed no-wash assays are particularly challenging because the amount of detection reagent present in the assay mixture increases, thus increasing the amount of ECL label in solution, contributing to high background ECL signals. The ECL coreactant described herein has surprisingly good discrimination between bound and free ECL labels in multiplexed assay formats, including multiplexed no-wash assays, providing high ECL signals and low background. In embodiments, the ECL coreactant is TEA.

[0210] In embodiments, the surface comprises multiple binding domains, and each binding complex is formed in a different binding domain. In embodiments, the multiple binding domains are on a single surface. In embodiments, the surface comprises a multiwell plate, and each binding domain is in a different well. In embodiments, the surface comprises a well of a multiwell plate, and each binding domain is in a separate portion of the well. In embodiments, the multiple binding domains are on one or more surfaces. In embodiments, the surface comprises particles, and each binding domain is on a different particle. In embodiments, the particles are arranged in a particle array. In embodiments, the particles are coded to allow identification of specific particles and to distinguish each binding domain.

[0211] In embodiments, each binding domain comprises a targeting agent capable of binding to the targeting agent complement, and each binding reagent comprises an auxiliary linking agent capable of binding to the linking agent. In embodiments, the binding reagents are immobilized within the binding domains by (1) binding the binding reagent to the targeting reagent complement connected to the linking agent via the auxiliary linking agent, and (2) binding the product of (1) to the binding domains comprising the targeting agents, where (i) each binding domain comprises a different targeting agent, and (ii) each targeting reagent complement selectively binds to one of the targeting reagents, thereby immobilizing each binding reagent to its associated binding domain.

[0212] In embodiments, an optional cross-linking agent, which is a binding partner of both the linking agent and the auxiliary linking agent, cross-links the linking agent and the auxiliary linking agent such that the binding reagents, each bound to its respective targeting agent complement, contact the binding domains and bind to their respective targeting agents via the cross-linking agent, the targeting agent complement on each binding reagent, and the targeting agent on each binding domain.

[0213] In embodiments, the targeting agent and the targeting agent complement are two members of a binding partner pair selected from avidin-biotin, streptavidin-biotin, antibody-hapten, antibody-antigen, antibody-epitope tag, nucleic acid-complementary nucleic acid, aptamer-aptamer target, and receptor-ligand. In embodiments, the targeting agent and the targeting agent complement are cross-reactive moieties, such as a thiol and maleimide or iodoacetamide, an aldehyde and hydrazide, or an azide and alkyne or cycloalkyne. In embodiments, the targeting agent is biotin and the targeting agent complement is avidin or streptavidin.

[0214] In embodiments, the linking agent and auxiliary linking agent are two members of a binding partner pair selected from avidin-biotin, streptavidin-biotin, antibody-hapten, antibody-antigen, antibody-epitope tag, nucleic acid-complementary nucleic acid, aptamer-aptamer target, and receptor-ligand. In embodiments, the linking agent and auxiliary linking agent are cross-reactive moieties, such as a thiol and maleimide or iodoacetamide, an aldehyde and hydrazide, or an azide and alkyne or cycloalkyne. In embodiments, the linking agent is avidin or streptavidin, and the auxiliary linking agent is biotin. In embodiments, the targeting agent and the targeting agent complement are complementary oligonucleotides. In embodiments, the targeting agent complement is streptavidin, the targeting agent is biotin, and the linking agent and auxiliary linking agent are complementary oligonucleotides.

[0215] In embodiments including a cross-linking agent, the cross-linking agent is streptavidin or avidin, and the linking agent and co-linking agent are each biotin.

[0216] In embodiments, the present disclosure provides methods for producing a composition comprising combining an ECL coreactant, an ionic component, and a surfactant. In embodiments, the ECL coreactant is tributylamine (TBA), (dibutyl)aminoethanol (DBAE), (diethyl)aminoethanol (DEAE), triethanolamine (TEA), butyldiethanolamine (BDEA), propyldiethanolamine (PDEA), ethyldiethanolamine (EDEA), methyldiethanolamine (MDEA), tert-butyldiethanolamine (tBDEA), dibutylamine (DBA), butylethanolamine (BEA), diethanolamine (DEA), dibutylamine propylsulfonate (DBA-PS), dibutylamine butylsulfonate (DBA-BS), butylethanolamine propylsulfonate (BEA-PS), butylethanolamine butylsulfonate (BEA-BS), diethanolamine propylsulfonate (DEA-PS), or diethanolamine butylsulfonic acid (DEA-BS, also known as 3-[bis-(2-hydroxyethyl)-amino]-propane-1-sulfonic acid).

[0217] In embodiments, the present disclosure further provides a method for producing a composition, comprising combining triethanolamine (TEA) and an ionic component. In embodiments, the present disclosure further provides a method for producing a composition, comprising combining triethanolamine (TEA), an ionic component, and a surfactant, wherein the method does not include adding an additional pH buffer component. In embodiments, one or more of the components are provided in dry form. Suitable ionic components and surfactants for the composition are provided herein, for example, NaCl, KCl, and LiCl (for the ionic component), and Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26-PEO5-PPO 26 (PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, and alkyl ether-polyethylene glycol (e.g., PEG(18) tridecyl ether) (in the case of surfactants). TEA, ionic components, and surfactants may be included at concentrations described herein. In embodiments, the composition produced by the present method includes about 1000 mM to about 6500 mM TEA, about 700 to about 1000 mM ionic components, and about 0.5 mM to about 10 mM surfactant. In an embodiment, the composition produced by the present method comprises about 1200 mM to about 1600 mM TEA, about 700 to about 1000 mM ionic components, and about 1 mM to about 5 mM surfactant.

[0218] In embodiments, the present disclosure further provides a method for producing a composition comprising combining tert-butyldiethanolamine (tBDEA), methyldiethanolamine (MDEA), 3-[bis-(2-hydroxyethyl)-amino]-propane-1-sulfonic acid (DEA-PS), or a combination thereof, an ionic component, and a surfactant. In embodiments, one or more of the components are provided in dry form. Suitable ionic components and surfactants for the composition are provided herein, for example, NaCl, KCl, and LiCl (for ionic components), and Poloxamer 407 (KOLLIPHOR® P-407), PEO 18 -PPO 72 -PEO 18 (PLURONIC® P-123), PEG5-PPG 68 PEG5 (PLURONIC® L-121), PPO 26 -PEO5-PPO 26(PLURONIC® 31R1), ethylenediaminetetrakis(propoxylate-block-ethoxylate)tetrol (TETRONIC® 701), polyethylene glycol dodecyl ether (BRIJ® L4), polyethylene glycol hexadecyl ether (BRIJ® 58), polysorbate 20 (TWEEN® 20), 2,4,7,9-tetramethyl-d-decyne-4,7-diol ethoxylate, and alkyl ether-polyethylene glycol (e.g., PEG(18) tridecyl ether) (in the case of surfactants). tBDEA and / or MDEA, ionic components, and surfactants may be included at concentrations described herein. In an embodiment, the composition produced by the present method comprises about 50 mM to about 250 mM tBDEA, about 50 mM to about 250 mM MDEA, and / or about 50 mM to about 250 mM DEA-PS, about 700 to about 1000 mM ionic components, and about 0.5 mM to about 10 mM surfactant.

[0219] Methods using ECL-labeled oligonucleotide probes In some embodiments of the methods disclosed herein, including those described above, the methods are a new type of molecular assay for sensitive and specific detection based on the use of ECL-labeled oligonucleotide probes. In embodiments, the probes contain a quenching moiety that quenches the ECL signal at least when the probe is not hybridized to a complementary oligonucleotide. In embodiments, the probes have a molecular beacon-like design. Without being bound by any theory, it is believed that the ECL signal is most efficiently generated near the surface of the electrode. In embodiments, immobilizing the ECL-labeled oligonucleotide probe on or near the electrode surface results in a higher signal compared to detecting the ECL-labeled oligonucleotide probe in solution. When the target oligonucleotide to which the ECL-labeled oligonucleotide probe hybridizes is immobilized on the surface, the ECL-labeled oligonucleotide probe is within the optimal excitation distance. Additionally, if the probe contains a quenching moiety, the method includes a step of dequenching the probe hybridized to the complementary oligo...

Claims

1. 1. An electrochemiluminescence (ECL) detection method comprising: a) providing a substrate comprising an electrode, the substrate having a binding reagent immobilized on a surface of the substrate; b) contacting the substrate with a composition, the composition comprising: i) a binding partner and / or binding complex comprising an oligonucleotide, said binding reagent binding said binding partner and / or binding complex; ii) a plurality of ECL-labeled oligonucleotide probes comprising oligonucleotide sequences complementary to the oligonucleotide sequences of the binding partners and / or binding complexes; iii) contacting with an ECL coreactant that is not TPA; c) hybridizing a portion of said plurality of ECL-labeled oligonucleotide probes to said oligonucleotides of said binding partners and / or binding complexes that are bound by said binding reagent, and another portion of said plurality of ECL-labeled oligonucleotide probes that are not hybridized to said oligonucleotides of said binding partners and / or binding complexes that are bound by said binding reagent; d) selectively dequenching the portion of the plurality of ECL-labeled probes hybridized to the oligonucleotides of the binding partners and / or binding complexes; and e) applying a voltage to the electrodes to generate ECL; f) measuring the ECL, wherein the portion of the plurality of ECL labeled oligonucleotide probes that are not hybridized to the oligonucleotides of the binding partner and / or binding complex are not removed from the composition prior to applying the voltage and measuring the ECL.

2. b) contacting the substrate with the composition b') contacting said substrate with a composition comprising said binding partner and / or binding complex; b'') contacting said substrate with a composition comprising said plurality of ECL-labeled oligonucleotide probes; 2. The method of claim 1, comprising: b''') contacting said substrate with a composition comprising said ECL coreactant.

3. The method of claim 2 , wherein each of steps b′), b″) and b′″) is performed sequentially.

4. The method of claim 2 , wherein at least two of steps b′), b″) and b′″) are performed simultaneously.

5. The method further comprising: b') contacting the substrate with a first composition comprising the binding partner and / or binding complex, and immobilizing the binding partner and / or binding complex on the surface by binding to the binding reagent; b'') contacting said substrate containing said immobilized binding partners and / or binding complexes with a second composition containing said plurality of ECL-labeled oligonucleotide probes and said ECL coreactant; or b') contacting the substrate with a first composition comprising the binding partners and / or binding complexes and the plurality of ECL-labeled oligonucleotide probes, wherein a portion of the plurality of ECL-labeled oligonucleotide probes are hybridized to the oligonucleotides of the binding partners and / or binding complexes, and immobilizing the binding partners and / or binding complexes on the surface by binding to the binding reagent; b'') contacting the substrate containing the immobilized binding partner and / or binding complex with a second composition containing the ECL coreactant; or b') contacting the substrate with a first composition comprising the binding partner and / or binding complex, and allowing the binding partner and / or binding complex to bind to the binding reagent, thereby immobilizing the binding partner and / or binding complex on the surface; b'') contacting the substrate containing the immobilized binding partners and / or binding complexes with a second composition containing the plurality of ECL-labeled oligonucleotide probes, allowing a portion of the plurality of ECL-labeled oligonucleotide probes to hybridize to the oligonucleotides of the immobilized binding partners and / or binding complexes; 2. The method of claim 1, comprising: b''') contacting said substrate with a third composition comprising said ECL coreactant.

6. 6. The method of any one of claims 1 to 5, further comprising washing the substrate after said contacting the substrate with said binding partners and / or binding complexes to remove binding partners and / or binding complexes not bound by said binding reagent, said washing being prior to contacting the substrate with said composition comprising said plurality of ECL-labeled oligonucleotide probes.

7. 1. An electrochemiluminescence (ECL) detection method comprising: a) providing a substrate comprising an electrode, the substrate having immobilized on a surface thereof a binding partner and / or a binding complex comprising an oligonucleotide; b) contacting the substrate with a composition, the composition comprising: i) a plurality of ECL-labeled oligonucleotide probes comprising oligonucleotide sequences complementary to the oligonucleotide sequences of the binding partners and / or binding complexes; ii) contacting with an ECL coreactant that is not TPA; c) hybridizing a portion of said plurality of ECL-labeled oligonucleotide probes to said oligonucleotides of said immobilized binding partners and / or binding complexes, wherein another portion of said plurality of ECL-labeled oligonucleotide probes is not hybridized to said oligonucleotides of said immobilized binding partners and / or binding complexes; d) selectively dequenching the portion of the plurality of ECL-labeled probes hybridized to the oligonucleotides of the binding partners and / or binding complexes; and e) applying a voltage to the electrodes to generate ECL; f) measuring the ECL, wherein the portion of the plurality of ECL labeled oligonucleotide probes that are not hybridized to the oligonucleotides of the binding partner and / or binding complex are not removed from the composition prior to applying the voltage and measuring the ECL.

8. b) contacting the substrate with the composition b') contacting said substrate with a composition comprising said plurality of ECL-labeled oligonucleotide probes; 8. The method of claim 7, comprising: b'') contacting said substrate with a composition comprising said ECL coreactant.

9. The method of claim 8 , wherein each of steps b′) and b″) is performed sequentially.

10. 9. The method of claim 8, wherein each of steps b') and b'') is performed simultaneously, and optionally, said plurality of ECL-labeled oligonucleotide probes and said ECL co-reactant are in a single composition.

11. The method of any one of claims 1 to 10, wherein the binding partner and / or binding complex comprises an analyte.

12. The method of claim 11 , wherein the analyte comprises a peptide.

13. The method of claim 11 , wherein the analyte comprises an oligonucleotide.

14. The method of claim 13, wherein the analyte is the binding partner and / or the oligonucleotide of the binding complex.

15. The method of any one of claims 11 to 13, wherein the analyte is labeled with the oligonucleotide.

16. 16. The method of claim 15, wherein the analyte is labeled with the oligonucleotide by binding the analyte to a detection reagent that comprises the oligonucleotide.

17. The method of any one of claims 1 to 16, wherein the oligonucleotides of the binding partners and / or binding complexes comprise multiple copies of the sequence complementary to the oligonucleotide sequences of the multiple ECL-labeled oligonucleotide probes.

18. 20. The method of claim 17, further comprising performing an amplification reaction prior to contacting the substrate with the plurality of ECL-labeled oligonucleotide probes to generate the plurality of copies of the sequence complementary to the oligonucleotide sequence of the plurality of ECL-labeled oligonucleotide probes.

19. 17. The method of claim 16, wherein the analyte is labeled with an oligonucleotide by combining the analyte with a detection reagent comprising an oligonucleotide primer, and the oligonucleotide primer is extended by a polymerase to generate the oligonucleotide comprising the multiple copies of the sequence complementary to the oligonucleotide sequence of the ECL-labeled oligonucleotide probe.

20. 20. The method of claim 18 or 19, wherein the amplification reaction or primer extension is a rolling circle amplification reaction.

21. the ECL-labeled oligonucleotide probe comprises a stem-loop or hairpin structure, an ECL label, and a quenching moiety that is adjacent to and quenches the ECL label when the oligonucleotide probe is in a stem-loop or hairpin configuration, but does not quench the ECL label when the stem-loop or hairpin structure is in an open configuration; 21. The method of any one of claims 1 to 20, wherein said selectively dequenching comprises hybridizing said portion of said plurality of ECL-labeled oligonucleotide probes to said binding partner and / or said oligonucleotide of a binding complex in an open configuration.

22. the ECL labeled oligonucleotide probe comprises an ECL label and a quenching moiety that is adjacent to the ECL label when the oligonucleotide probe is in a linear configuration and quenches the ECL label; 21. The method of any one of claims 1 to 20, wherein the selectively dequenching comprises selectively cleaving the quenching moiety from only the portion of the plurality of ECL labeled probes hybridized to the oligonucleotide of the binding partner and / or binding complex, such that the quenching moiety is released into solution and is no longer in proximity to the ECL labels of the hybridized ECL labeled probes that remain hybridized to the oligonucleotide of the binding partner and / or binding complex after cleavage of the quenching moiety.

23. 23. The method of claim 22, wherein the cleavage is carried out by an enzyme.

24. 24. The method of claim 23, wherein the enzyme is selected from the group consisting of a nicking restriction endonuclease, RNase H2, and a polymerase with 5' exonuclease activity.

25. 25. The method of claim 23 or 24, wherein the enzyme cleaves only the ECL-labeled oligonucleotide probe, leaving the binding partner and / or the oligonucleotide of the binding complex intact.

26. 26. The method of claim 25, wherein the enzyme is a nicking restriction endonuclease that recognizes a sequence within the hybridized ECL-labeled probe, or RNase H2 that recognizes an RNA base within the hybridized ECL-labeled probe.

27. the enzyme is a polymerase having 5' exonuclease activity, and the method comprises: hybridizing a primer to the oligonucleotide of the binding partner and / or binding complex at the 5' position of the hybridized ECL-labeled probe; allowing the polymerase having 5' exonuclease activity to extend the primer to the hybridized ECL-labeled probe, wherein the 5' exonuclease activity cleaves the quenched portion of the hybridized ECL-labeled probe; 24. The method of claim 23, wherein the ECL-labeled probe comprises a portion that is resistant to the 5' exonuclease activity.

28. The ECL coreactant may be 3-(di-n-propylamino)-propanesulfonic acid, 4-(di-n-propylamino)-butanesulfonic acid, 4-[bis-(2-hydroxyethane)-amino]-butanesulfonic acid, piperidine-N-(3-propanesulfonic acid), azepane-N-(3-propanesulfonic acid), piperidine-N-(3-propanesulfonic acid) (PPA), 3-morpholino-2-hydroxypropanesulfonic acid (M OPSO), 3-morpholinepropanesulfonic acid (MOPS), N-(2-hydroxyethyl)piperazine-N'-3-propanesulfonic acid (EPPS), N-(2-hydroxyethyl)piperazine-N'-3-ethanesulfonic acid (BES), piperazine-N,N'-bis(2-ethanesulfonic acid) (PIPES), triethanolamine (TEA), N-2-hydroxypiperazine-N-2-ethanesulfonic acid (HEPE), S), piperazine-N,N'-bis-4-butanesulfonic acid, homopiperidine-N-3-propanesulfonic acid, piperazine-N,N'-bis-3-propanesulfonic acid, piperazine-N-3-propanesulfonic acid, piperazine-N-2-hydroxyethane-N'-3-methylpropanoate, piperazine-N,N'-bis-3-methylpropanoate, 1,6-diaminohexane-N,N,N',N'-tetraacetic acid, N,N- Bispropyl-N-4-aminobutanesulfonic acid, N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid (TES), 1,3-bis[tris(hydroxymethyl)methylamino]propane (bis-trispropane), 3-dimethylamino-1-propanol, 3-dimethylamino-2-propanol, N,N,N',N'-tetrapropylpropane-1,3-diamine (TPA dimer), piperazine-N,The method according to any one of claims 1 to 27, wherein the hydroxyl group is selected from the group consisting of N'-bis(2-hydroxypropane)sulfonic acid (POPSO) and 2-hydroxy-3-[4-(2-hydroxyethyl)piperazin-1-yl]propane-1-sulfonic acid (HEPPSO), N-butyldiethanolamine (BDEA), 2-dibutylaminoethanol (DBAE), tert-butyldiethanolamine (tBDEA), methyldiethanolamine (MDEA), 3-[bis-(2-hydroxy-ethyl)-amino]-propane-1-sulfonic acid (DEA-PS), and combinations thereof.

29. 28. The method of any one of claims 1-27, wherein the ECL coreactant is TEA or is selected from the group consisting of TEA, BDEA, MDEA, DEA-PS, and combinations thereof.

30. 30. The method of any one of claims 1 to 29, wherein the quenching moiety is selected from the group consisting of ATTO 540Q, ATTO 575Q, ATTO 580Q, ATTO 612Q, Iowa Black FQ, Iowa Back RQ, QSY 21, IRDye QC-1, BHQ0, BHQ1, BHQ-2, BHQ-3, dabcyl, QSY 7, QSY 9, QSY 21, QSY 35, QXL 490, QXL 520, QXL 570, QXL 670, ferrocene, iron bipyridine, and combinations thereof.

31. The method of any one of claims 1 to 30, wherein the ECL label is an organometallic complex containing ruthenium, osmium, iridium, rhenium, and / or a lanthanide metal.

32. 32. The method of any one of claims 1 to 31, wherein the ECL label comprises tris(bipyridine)ruthenium or modified tris(bipyridine)ruthenium.

33. The ECL label has the formula II: 【Chemistry 7】 33. The method of claim 32, comprising the chemical structure shown in (II).

34. 34. The method of any one of claims 1 to 33, wherein the co-reactant is in the composition of any one of numbered items 1 to 69.

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