Detection assembly

Abstract

The present disclosure provides a sensing assembly (100) for sensing an analyte. The sensing assembly includes a plurality of test electrodes (102) configured to provide signals from a plurality of independent measurements in response to the analyte. Alternatively or additionally, the plurality of test electrodes are configured to generate different transient responses in response to a given concentration of the analyte.

Description

Technical Field

[0001] The present disclosure relates to a detection assembly for detecting an analyte, such as a biosensor or a chemical assay, a detection assembly for detecting a plurality of different analytes, and a system and method for determining the concentration of an analyte in a sample matrix.

Background Art

[0002] Designs of various biosensors and chemical assays for detecting analytes are known. Analytes can include, for example, biomarkers such as hormones established to assist in patient monitoring and / or diagnosis.

[0003] For example, in a standard enzyme-linked immunosorbent assay (ELISA) used for quantifying analytes such as peptides, proteins, antibodies, hormones, etc., a recognition element for selectively interacting, for example, binding with the analyte of interest is immobilized on a suitable support. For example, an antigen is immobilized on a support and then complexed with an antibody linked to an enzyme.

Summary of the Invention

Problems to be Solved by the Invention

[0004] In biosensors and assays such as ELISA, it has been found that quantitative measurement of analytes over a wide range of concentrations is difficult. Typically, there is a trade-off between sensitivity and the range of concentrations that can be detected.

Means for Solving the Problems

[0005] The present disclosure provides a detection assembly for detecting an analyte. The detection assembly includes a plurality of test electrodes configured to provide signals from a plurality of independent measurements in response to the analyte. Alternatively or additionally, the plurality of test electrodes are configured to generate different transient responses in response to a given concentration of the analyte.

[0006] In a particular embodiment, a sensing assembly comprising a test electrode device is provided. The test electrode device includes a plurality of test electrodes. Each test electrode has an analyte-interacting portion configured to selectively interact with an analyte. A saturation limit is defined for each test electrode at which the analyte-interacting portion is saturated with the analyte. Each saturation limit is defined between the test electrodes. different The detection assembly further comprises a set of control electrodes providing a set of control electrode regions, each control electrode region configured to provide a control measurement independent of the analyte. Each control electrode region is provided for one of the test electrodes.

[0007] In a particular embodiment, a detection assembly is provided for detecting multiple analytes that are different from each other. The detection assembly comprises a first test electrode device. The first test electrode device comprises a plurality of first test electrodes. Each of the first test electrodes comprises a first analyte interaction portion configured to selectively interact with a first analyte. A first saturation limit, at which the first analyte interaction portion is saturated with the first analyte, is defined for each of the first test electrodes. Each first saturation limit is defined between the first test electrodes. different The detection assembly further comprises a second test electrode device and a second set of control electrodes. The second test electrode device comprises a plurality of second test electrodes. Each of the second test electrodes comprises a second analyte interaction portion configured to selectively interact with a second analyte different from the first analyte. A second saturation limit is defined for each of the second test electrodes, at which point the second analyte interaction portion is saturated with the second analyte. Each second saturation limit is defined between the second test electrodes. different The detection assembly further comprises at least one set of control electrodes providing a set of control electrode regions, each control electrode region configured to provide a control measurement independent of the analyte. Each control electrode is provided for one of the first test electrodes and / or one of the second test electrodes.

[0008] In a particular embodiment, a system is provided for determining the concentration of an analyte in a sample matrix. The system comprises a detection assembly for detecting the analyte. The detection assembly comprises a test electrode device. The test electrode device comprises a plurality of test electrodes. Each test electrode has an analyte-interacting portion configured to selectively interact with the analyte. A saturation limit is defined for each test electrode at which the analyte-interacting portion is saturated with the analyte. The respective saturation limits are defined between the test electrodes. different The detection assembly further comprises a set of control electrodes providing a set of control electrode regions, each control electrode region configured to provide a control measurement independent of the analyte. Each control electrode region is provided for one of the test electrodes. The system comprises a signal processing unit and a concentration determination unit. The signal processing unit is configured to process signals received from multiple test electrodes and signals received from the set of control electrode regions. The concentration determination unit is configured to determine the concentration of the analyte in the sample matrix based on the signals processed from the multiple test electrodes and the signals processed from the set of control electrode regions.

[0009] In a particular embodiment, a method is provided for determining the concentration of an analyte in a sample matrix. The method includes processing signals received from a plurality of test electrodes. Each test electrode comprises an analyte-interacting portion configured to selectively interact with the analyte. A saturation limit is defined for each test electrode at which the analyte-interacting portion is saturated with the analyte, and the respective saturation limits are between the test electrodes. differentThe method includes processing signals received from a set of control electrodes. The set of control electrodes provides a set of control electrode regions, each control electrode region configured to provide a control measurement independent of the analyte. Each control electrode region is provided for one of the test electrodes. The method further includes determining the concentration of the analyte in the sample matrix based on the signals processed from multiple test electrodes and the signals processed from the set of control electrode regions.

[0010] Herein, the present invention will be described in more detail with reference to the accompanying drawings, which are not intended to limit the scope of the invention. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 provides a schematic plan view of a detection assembly according to the embodiment. [Figure 2] Figure 2 provides a graph of the sensor signal versus time for the detection assembly shown in Figure 1. [Figure 3] Figure 3 provides schematic plan views of electrodes of different areas, and a schematic diagram of the immobilization of captured species on the electrodes. [Figure 4] Figure 4 schematically shows analytic detection using a detection assembly according to another embodiment when the analytic concentration in the sample matrix is ​​relatively high. [Figure 5] Figure 5 provides a graph of the sensor signal versus time for the detection assembly and sample matrix shown in Figure 4. [Figure 6] Figure 6 schematically illustrates analyte detection using the detection assembly shown in Figure 4 when the analyte concentration in the sample matrix is ​​relatively low. [Figure 7] Figure 7 provides a graph of sensor signals versus time for the detection assembly and sample matrix shown in Figure 6. [Figure 8] Figure 8 provides simplified graphs of sensor signals versus time for higher analyte concentrations (left graph) and lower analyte concentrations (right graph). [Figure 9] FIG. 9 provides a schematic plan view of a set of control electrodes according to an embodiment. [Figure 10] FIG. 10 schematically shows a test electrode according to an embodiment. [Figure 11] FIG. 11 schematically shows an exemplary detection assembly for detecting a plurality of different analytes. [Figure 12] FIG. 12 provides a block diagram of a system according to an embodiment. [Figure 13] FIG. 13 shows a flowchart of a method according to an embodiment. [Figure 14] FIG. 14 provides a view of an exemplary test electrode device having a test electrode unit and sub-units. [Figure 15] FIG. 15 provides a schematic plan view of a test electrode unit and sub-units according to another embodiment, and a schematic view of immobilization of capture species on the test electrode sub-unit. [Figure 16] A view of a detection assembly according to a further embodiment is provided. [Figure 17] A view of a detection assembly according to a further embodiment is provided. [Figure 18] A view of a detection assembly according to a further embodiment is provided. DETAILED DESCRIPTION OF THE INVENTION

[0012] A variety of analyte detection techniques that utilize analyte binding technology are known. Capture species that are specific for a particular analyte, or in other words, ligands, can be used to bind to the analyte. Such binding can be detected by a variety of methods such as colorimetry, fluorescence, or electrochemistry.

[0013] Quantitative measurement of analytes over a wide range of concentrations is a challenge. Typically, there is a trade-off relationship between sensitivity and the range of concentrations that can be detected.

[0014] Certain embodiments of the present disclosure provide a detection assembly for detecting an analyte. Such a detection assembly may include a test electrode device having a plurality of test electrodes, each of the test electrodes having an analyte interaction portion configured to selectively interact with the analyte.

[0015] The plurality of test electrodes may be configured to provide signals from a plurality of independent measurements in response to the analyte. Alternatively or additionally, the plurality of test electrodes may be configured to generate different transient responses in response to a given concentration of the analyte.

[0016] For example, rather than relying only on equilibrium data or endpoint data, multiple signal inputs may be used to determine the analyte concentration.

[0017] Without wishing to be bound by any particular theory, in at least some embodiments, such a plurality of test electrodes may assist in providing a detection assembly with a wider dynamic range, in other words, a wider range from the lowest concentration to the highest concentration of analyte that can be reliably detected by the detection assembly. Alternatively or additionally, in some embodiments, the plurality of test electrodes providing multiple measurement signals, such as multiple independent measurement signals, can assist in providing higher accuracy in determining the analyte concentration.

[0018] In certain embodiments of the present disclosure, each saturation limit is different The saturation limit at which the analyte interaction portion of each test electrode is saturated with the analyte is defined by the analyte concentration in the sample matrix. This can be shown by the fact that, under otherwise identical conditions, the signal of each test electrode does not change further even when in contact with an analyte concentration higher than the analyte concentration that defines the saturation limit.

[0019] In some embodiments, the saturation limit can be considered as the ability of each test electrode to bind to the analyte. In other words, the saturation limit can be reached when all available parts of the analyte-interacting portion interact, for example, with the analyte.

[0020] As used herein, the terms “analyte concentration” or “analyte concentration” may, in certain embodiments, refer to the activity of the analyte. Analyte activity can provide a measure of the effective concentration of the analyte in the sample matrix. Activity is useful, for example, for considering analyte-analyte interactions in the sample matrix, and may be more relevant at higher analyte concentrations. Nevertheless, the above-specified term “concentration” is used herein for convenience.

[0021] The upper concentration limit of the detection assembly can be extended by using a test electrode apparatus that includes a test electrode with a higher saturation limit. Furthermore, the rate of change of the signal may also depend on the analyte concentration. Different transient responses to a given analyte concentration may be observed from a test electrode with a lower saturation limit compared to a test electrode with a higher saturation limit.

[0022] It should be noted that in at least some biosensor / assay configurations, the so-called "hook effect" is observed at analyte concentrations exceeding the saturation limit. The measured or observed concentration may actually begin to decrease at such high analyte concentration regimes.

[0023] In some embodiments, including a test electrode with a higher saturation limit in the sensing assembly can help facilitate the transition to higher analyte concentrations in high analyte concentration regimes where such a hook effect is observed.

[0024] Analytes can be selected from, for example, molecular species, metal ions, viruses, and microorganisms. Biomarkers such as cytokines or hormones are specifically mentioned because they are relevant in the context of patient monitoring and diagnostic testing. Analytes may be hormones selected from, for example, eicosanoids, steroids, amino acids, amines, peptides, or proteins.

[0025] In non-limiting embodiments, the analyte interaction portion is defined by a capture species provided adjacent to the surface of each test electrode. In such embodiments, the capture species is configured to selectively interact with the analyte.

[0026] For this purpose, any suitable capture species can be selected according to the analyte intended to be detected by the detection assembly. For example, the capture species may include an antibody that is specific to a particular antigen. In such examples, the analyte may take the form of an antigen.

[0027] More generally, in some embodiments, the capture species may include at least one selected from proteins, peptides, carbohydrates, and nucleic acids.

[0028] The protein may be an enzyme, for example, an enzyme that is specific to the analyte. In other, less limiting embodiments, the protein may be an antibody. In the latter case, the analyte may be an antigen to which the antibody selectively binds.

[0029] The capture species may, for example, include or be defined by an antigen. In this case, the analyte may be a species such as an antibody that is selectively bound by the antigen-capturing species. The antigen may be, for example, a protein, peptide, polysaccharide, or carbohydrate such as a sugar chain, or may include such a substance.

[0030] In one embodiment, the capture species includes an aptamer. The aptamer may be defined as an oligonucleotide or peptide configured to bind to the analyte. Such an aptamer may be configured to interact with, for example, bind to, various types of analytes, such as small molecules, e.g., amino acids or amines, proteins, metal ions, and microorganisms.

[0031] In some non-limiting embodiments, the aptamer is functionalized with an electroactive moiety, such as a redox-active moiety, which selectively interacts with the analyte, for example, a change in the aptamer's stereochemistry upon binding, causing a change in the proximity of the electroactive moiety to the surface of each test electrode.

[0032] In particular, in embodiments where the test electrode is configured to determine a change in current associated with selective interaction with the analyte, such changes in the proximity of the electroactive portion to the surface of each test electrode may cause, or at least contribute to, the determined change in current. Therefore, aptamers functionalized with such electroactive portions can assist in the detection of current measurements of the analyte.

[0033] The interaction, for example, binding of the aptamer to the analyte results in a change in proximity, which may, for example, bring the electroactive portion closer to the surface of each test electrode than when the aptamer is not interacting with the analyte. In such embodiments, the interaction between the analyte and the aptamer may accelerate electron transfer between the electroactive portion and each test electrode, contributing to an increase in the current within each test electrode.

[0034] In alternative, non-limiting embodiments, changes in proximity resulting from the aptamer's interaction with the analyte, such as binding, may result in the electroactive portion moving further away from the surface of each test electrode than when the aptamer is not interacting with the analyte.

[0035] In such embodiments, the aptamer may be considered to be sterically configured in the absence of the analyte such that an electroactive portion, for example, a redox-active portion, is close to or in contact with the surface of the test electrode, thereby providing a baseline signal.

[0036] In such cases, a decrease in the current at each test electrode can be observed depending on the interaction between the analyte and the aptamer. Therefore, the higher the concentration of the analyte, the greater the decrease in current. Specific, non-limiting examples of this are described below with reference to Figures 4 to 8.

[0037] For this purpose, any suitable electroactive moiety may be contained in an aptamer such as methylene blue.

[0038] In some embodiments, the surface of each test electrode is functionalized with a capture species. Such functionalization can be achieved in any preferred way, such as by immobilizing the capture species on the surface by covalent or non-covalent bonds.

[0039] For example, thiol-terminated trapping species, such as thiol-terminated aptamers, can be immobilized, for example, grafted, onto the surface of a precious metal electrode, such as gold.

[0040] In a particular embodiment, a parameter relating to the amount of captured species for each test electrode determines the saturation limit of each test electrode. Thus, for example, different amounts of captured species are provided fixed on each test electrode.

[0041] For example, when the surface of a test electrode is functionalized with a captured species, the parameter may include the region of the surface that is functionalized with the captured species.

[0042] Such surface area of ​​a surface functionalized with a capture species difference This can be achieved by any preferred method. In non-limiting embodiments, the conductive region of the test electrode is in the test electrode apparatus. different In this way, the saturation limit of the test electrode is the conductive region functionalized with (at least) the captured species. difference As a result different .

[0043] In such embodiments, the surface area functionalized with the captured species may correspond to the conductive region of each test electrode.

[0044] Test electrodes having different regions may be arranged in an array, for example, with the test electrodes being arranged in an order of increasing region. Such an array may be considered, for example, an analyte titration platform.

[0045] For example, any suitable saturation limit of the test electrode according to the desired dynamic range of the sensing assembly. difference This may be considered. For example, the test electrode may be configured to enable detection of analyte concentration over a range scaled logarithmically.

[0046] In non-limiting embodiments, the functionalization of each conductive region in the captured species may be uniform for each test electrode. This may allow the same protocol for functionalizing the test electrodes, e.g., the same reagent drop size, reagents, washing, etc., to be used for each test electrode in the test electrode apparatus. Thus, it may be possible to use the same protocol for functionalizing the test electrodes, e.g., the same reagent drop size, reagents, washing, etc. for each test electrode in the test electrode apparatus. different The saturation limit can be determined by the conductive regions of different sizes.

[0047] Relatively high analyte concentrations may saturate smaller test electrodes, but not larger ones. The rate of signal change can also depend on the concentration, as mentioned above. Therefore, the generated data, such as the signal change from smaller to larger electrodes, and the rate of signal change, can be used to quantify the analyte.

[0048] In embodiments where the captured species includes an aptamer, and the electroactive portion of the aptamer moves away from the surface of each test electrode due to a change in proximity resulting from the aptamer's interaction with the analyte, for example, binding, a current can be generated at the test electrode when the analyte does not interact with the aptamer.

[0049] The larger the surface area of ​​the test electrode, the more trapping molecules may be immobilized on its surface, resulting in a larger starting current for the virgin test electrode, where the analyte has not yet interacted with the aptamer.

[0050] In other non-limiting embodiments, the area of ​​the surface functionalized with the captured species may be within the conductive region of each test electrode and therefore may not correspond to the conductive region. In such embodiments, the analyte-interacting portion may terminate at a boundary. This boundary can be identified using a preferred technique, such as a nuclear microscope. The area of ​​the analyte-interacting portion demarcated by the thus identified boundary can then be determined.

[0051] Alternatively or additionally to a parameter including the surface area functionalized with the captured species, the parameter may include the density of the captured species on the surface of the test electrode. A higher density of the captured species on the surface may help provide a larger saturation limit for each test electrode.

[0052] The density of trapped species on the surface of the test electrode difference This involves controlling the concentration of the solution used to functionalize the surface with a capture species, such as an aptamer. difference This can be carried out in any preferred method, such as by allowing the process to proceed. A more concentrated solution may provide a higher density of trapped species on the surface of each test electrode, for example, a packing density.

[0053] In some embodiments, the captured species may be held adjacent to the surface by a film. The film allows the analyte to pass through it, thereby allowing the analyte to be captured by the captured species positioned between the test electrode surface and the film. Non-limiting embodiments of this are described below with reference to Figure 10.

[0054] In such non-limiting embodiments, where the captured species are arranged between the surface of each test electrode and such a film, the parameters may include the concentration of the captured species in the solution provided between the film and the surface. Therefore, the concentration of the captured species for each of the test electrodes is difference By doing so, the saturation limit of the test electrode is different obtain.

[0055] In some embodiments, the test electrode apparatus comprises multiple units, each unit defining one of the test electrodes and comprising several test electrode subunits. In such embodiments, the number of test electrode subunits within each unit determines, at least in part, the saturation limit of each test electrode.

[0056] It should be noted that the test electrode subunit parameters relating to the amount of captured species for each test electrode subunit can further contribute to determining the saturation limit of each test electrode. Therefore, the more general description provided above regarding the parameters relating to the amount of captured species for each test electrode is applicable to test electrode subunits. The test electrode subunit parameters may include, for example, at least one of the surface area of ​​each test electrode subunit functionalized with the captured species, and the density of the captured species on the surface of each test electrode subunit.

[0057] At least some of the test electrode subunits, and each of them in some embodiments, may have the same area as the others. This may make it possible, for example, to use the same reagent drop size, reagents, washing, etc., for each of these test electrode subunits. Nevertheless, the saturation limit is (at least) between units because the number of test electrode subunits contained in each unit is different. different Non-limiting embodiments of such test electrode devices are described below with reference to Figures 14 and 15.

[0058] In some non-limiting embodiments, each unit, and possibly one or more test electrode subunits within a unit, may be individually addressable. This can help improve the configurability of the test electrode apparatus.

[0059] More generally, the test electrode may include, or be formed from, any conductive material suitable for use in a sensing assembly, such as a precious metal, e.g., gold or platinum, or titanium nitride.

[0060] More generally, at least some important aspects of the embodiments of this disclosure are that, for example, having different regions functionalized with a capture species, multiple sites having different saturation limits may enable the determination of a wider range of concentrations.

[0061] In at least some embodiments of the present disclosure, the sensing assembly further comprises a set of control electrodes providing a set of control electrode regions, each control electrode region configured to provide a control measurement independent of the analyte. In such embodiments, each control electrode region is provided for one of the test electrodes.

[0062] For example, each control electrode region may include an analyte interaction portion configured to selectively interact with the analyte. In this way, each control electrode region may enable control measurements that are independent of the analyte and, in particular, independent of the analyte concentration.

[0063] A set of control electrodes can be arranged in any preferred manner, such as in the form of an array. In embodiments in which the test electrodes are also arranged in an array, the test electrode array and the control electrode array may extend parallel to each other, for example.

[0064] In a particular embodiment, the control electrode regions are relative to each other. different Such as in the control electrode region difference However, a set of control electrodes can help provide a control device for each of the test electrodes.

[0065] More generally, a test electrode device and a set of control electrodes are arranged to receive a sample matrix. The sample matrix, such as blood, urine, sweat, or tears, may (potentially) contain the analyte.

[0066] In some non-limiting embodiments, the test electrode apparatus and a set of control electrodes are mounted on a common substrate, such as a common semiconductor substrate like a silicon wafer. An example of this is described below with reference to Figure 1.

[0067] In an alternative embodiment, the test electrode device is mounted on a first substrate, such as a first semiconductor substrate, and a pair of control electrodes is mounted on a second substrate, such as a second semiconductor substrate, such as a (second) silicon wafer.

[0068] The test electrode device and a set of control electrodes may be placed, for example, in a suitable container or fluid engineering system, such as a microfluidic system. The sample matrix is ​​received in the container or fluid engineering system and can therefore be in contact with the test electrode device and the set of control electrodes.

[0069] In some embodiments, the control electrode region is configured for non-selective interaction with the sample matrix. In such embodiments, a set of control electrodes may be considered to provide negative control measurements. Such negative control measurements can determine, for example, one or more signals associated with non-selective interaction between the sample matrix and the control electrode region, e.g., nonspecific binding.

[0070] In non-limiting embodiments, the control electrode region is functionalized with a control aptamer configured not to interact with the analyte. For example, such a control aptamer may include an electroactive moiety, such as a redox active moiety.

[0071] For example, the electroactive portion of a control aptamer may be located proximal to the surface of each control electrode region, and since the control aptamer does not interact with the analyte, the signal associated with the control electrode region, such as the current signal, may remain constant, or at least substantially constant, in the presence of the analyte. Thus, each control electrode region in this non-limiting embodiment may be configured to provide a control measurement independent of the analyte. The term "substantially constant" in this context takes into account the relatively small signal change resulting from the contact of the sample matrix with the control electrode region.

[0072] The behavior of such control aptamer-functionalized control electrode regions, for example, the current measurement behavior, is in contrast to, for example, the behavior of the aptamer-functionalized test electrode described above. In embodiments where the interaction between the analyte and the aptamer causes the electroactive portion to move toward the surface of each test electrode, the current may increase in the presence of the analyte. In alternative embodiments where the interaction between the aptamer and the analyte causes the electroactive portion to move away from the surface of each test electrode, the current may decrease in the presence of the analyte. Different current measurement behaviors of the test electrode and control electrode regions are described in more detail hereby with reference to Figures 4 to 8.

[0073] It should be noted that any suitable electroactive moiety may be included in a control aptamer such as methylene blue.

[0074] In certain embodiments, the control electrode region is configured to selectively interact with non-analyte species present in the sample matrix. In such embodiments, a set of control electrodes may be considered to provide a positive control measurement. Such a positive control measurement may be based on interactions with common / ubiquitous species in the sample matrix, such as hemoglobin if the sample matrix contains or is blood, or urea if the sample matrix contains or is urine.

[0075] More generally, the control electrode region difference This may allow for increasing the size and ordering of the control electrode region, reaching the saturation limit. difference This may increase the saturation limit and allow for further sequencing of the test electrodes.

[0076] Therefore, a series of test electrode-control electrode region pairs can be defined according to ordering and further ordering such that the smallest control electrode region is paired with a test electrode having the smallest saturation limit, and the largest control electrode region is paired with a test electrode having the largest saturation limit.

[0077] Such a series of test electrode-control electrode region pairs can be arranged in any preferred manner. For example, the series may extend linearly on the surface of a common substrate, such as a common semiconductor substrate.

[0078] In the embodiment, for a series of consecutive test electrode-control electrode region pairs, an incremental change in the control electrode region corresponds to a further incremental change in the saturation limit of the test electrode. difference The control electrode region corresponding to difference For example, the saturation limit of the test electrode difference Because it is equal to or proportional to the test electrode signal, it can support a significant comparison between the test electrode signal and the control electrode signal for each test electrode-control electrode pair.

[0079] In this way, the contributions to the signal from the analyte interaction portion of the test electrode and the selective interaction of the analyte can be appropriately distinguished from such signal contributions that may simply be attributed to the sample matrix.

[0080] In this embodiment, each control electrode region corresponds to the surface area of ​​one of the test electrodes functionalized with the captured species.

[0081] The area of ​​the test electrode functionalized with the captured species differentIn non-limiting embodiments, the control electrode region may be identical to, for example, the area functionalized with one of the capture species of the test electrodes.

[0082] In certain non-limiting embodiments, the sensing assembly includes a series, for example, a pair of test-control electrode regions, where the test electrode has various regions functionalized with a capture species, such as an aptamer. For each pair, the control electrode region may be identical to, for example, the region of the test electrode functionalized with the capture species.

[0083] This region may have a diameter ranging from 1 μm to 500 μm, for example, 10 μm to 100 μm.

[0084] The region can determine the generated absolute signal. This means that a single analyte concentration in the sample matrix can generate multiple signal inputs, for example, the absolute change in the signal from a smaller area test electrode-control electrode region pair to a larger area test electrode-control electrode region pair, and the rate of change in the signal, which can then be inversely superimposed and integrated to obtain an analyte of a specific concentration.

[0085] More generally, a set of control electrodes may include or be formed from any suitable conductive material, such as a precious metal, gold or platinum, or titanium nitride.

[0086] In some embodiments, a pair of control electrodes includes a plurality of individually addressable portions, such as conductive portions. In such embodiments, each control electrode region can be defined by addressing one or more of the plurality of portions.

[0087] Therefore, for example, by addressing / activating one or a particular combination of those parts via a suitable switching device, it may be possible to select each control electrode region. The control electrode regions may be selected according to the saturation limit of one of the test electrodes, as described above.

[0088] Multiple portions may be arranged in any preferred manner, such as in the form of concentric, elliptical, or arc-shaped portions, and / or as multiple intersecting portions, as in the non-limiting embodiment shown in Figure 9. Such arrangement can help save space on the substrate where, for example, a set of control electrodes are located.

[0089] The analyte detection assembly may be compatible with any preferred detection method, such as electrochemical detection or principle detection. In some embodiments, the analyte detection assembly comprises an electrochemical cell including a working electrode assembly and a counter electrode. In such embodiments, the working electrode assembly may include a test electrode device.

[0090] Therefore, the test electrode device may be configured to determine the change in current associated with the selective interaction with the analyte. Such detection of current-measuring analytes is mentioned in the context of some of the non-limiting embodiments described above.

[0091] The working electrode assembly may also include a pair of control electrodes. Thus, the pair of control electrodes may be configured to determine changes in the current associated with the sample matrix in contact with the control electrode region.

[0092] The counter electrode can act as either a positive or negative electrode to the working electrode assembly, such as a test electrode device and a set of control electrodes.

[0093] In some embodiments, the electrochemical cell further comprises a reference electrode. The reference electrode may constitute a site for a known chemical reaction having a known redox potential. Any suitable reference electrode may be used, such as a saturated calomel, silver / silver chloride, or copper / copper sulfate reference electrode.

[0094] The fixed redox potential of the reference electrode can provide a reference point for the redox potential of the working electrode assembly. The potential generated within the electrochemical cell is derived from the working electrode assembly, and the current can be measured via the potential of the working electrode assembly set relative to the fixed potential of the reference electrode. For example, signals / signal changes arising from the interaction between the analyte and the analyte interaction portion of the test electrode and / or the interaction between the sample matrix and the control electrode region can be generated in the external circuitry of the electrochemical cell from this potential difference.

[0095] In some embodiments, the sensing electrode assembly may comprise, for example, a capacitance and / or impedance determination assembly as a substitute for or in addition to the electrochemical cell described above. Thus, the principle of the present disclosure may be implemented, for example, in the form of a capacitive and / or impedance sensing array.

[0096] Such a capacitance and / or impedance determination assembly includes a further electrode device, wherein at least some of the test electrodes of the test electrode device may be spaced apart from the further electrode device to enable determination of capacitance and / or impedance between those at least some of the test electrodes and the further electrode device.

[0097] Further electrode devices can take any preferred form. In some non-limiting embodiments, the further electrode device itself includes one or more test electrodes such that each of the spatially separated "plates" of the capacitance and / or impedance determination assembly includes an analyte interaction portion. Examples of this are described below with reference to Figures 16-18. In other non-limiting embodiments, the further electrode device does not include such an analyte interaction portion and may be defined, for example, by a non-functionalized electrode.

[0098] The capacitance and / or impedance determination assembly further comprises a pair of control electrodes, the pair of control electrodes being spaced apart from the further electrode device to enable determination of capacitance and / or impedance between the pair of control electrodes and the further electrode device.

[0099] In a particular embodiment, a system for determining the concentration of an analyte in a sample matrix comprises a detection assembly according to any embodiment or example described herein, and a signal processing unit configured to process signals received from a plurality of test electrodes and signals received from a set of control electrode regions. The system further includes a concentration determination unit configured to determine the concentration of an analyte in the sample matrix based on the signals processed from the plurality of test electrodes and the signals processed from the set of control electrode regions.

[0100] In at least some embodiments, the system's concentration determination unit is configured to determine the concentration of the analyte based on one or more differential signals between signals processed from multiple test electrodes and signals processed from a set of control electrode regions.

[0101] In a particular embodiment, the concentration determination unit may be configured to determine the concentration based on (at least) the absolute change in the signal in the test electrode-control electrode pair and the rate of change in the signal.

[0102] The signal processing unit and the concentration determination unit may be implemented in any preferred manner using software and / or hardware to perform various required functions. One or both of the units may perform the required functions using one or more microprocessors programmed, for example, using software (e.g., microcode). Examples of processor components that may be used in various embodiments of this disclosure include, but are not limited to, conventional microprocessors, application-specific integrated circuits (ASICs), and field-programmable gate arrays (FPGAs).

[0103] In various implementations, one or both of the signal processing unit and / or the concentration determination unit may be associated with one or more non-temporary storage media, such as volatile and non-volatile computer memory, including RAM, PROM, EPROM, and EEPROM. The non-temporary storage media may be encoded with one or more programs that, when executed on one or more processors and / or controllers, perform the necessary functions. The various storage media may be fixed within the processor or controller, or they may be transportable so that one or more programs stored on the storage media can be loaded into the signal processing unit and / or the concentration determination unit.

[0104] In some non-limiting embodiments, the system includes a user interface, such as a display, for communicating the analyte concentration determined by the concentration determination unit.

[0105] Alternatively or additionally, the system may include a communication interface device, such as a wireless transmitter, configured to transmit the analyte concentration determined by the concentration determination unit to an external device such as a personal computer, tablet, smartphone, or remote server.

[0106] In a particular embodiment, the detection assembly is configured to detect multiple different analytes. In such an embodiment, the detection assembly comprises a first test electrode device. The first test electrode device comprises a plurality of first test electrodes. Each of the first test electrodes comprises a first analyte interaction portion configured to selectively interact with a first analyte. A first saturation limit is defined for each of the first test electrodes, at which point the first analyte interaction portion is saturated with the first analyte. Each first saturation limit is defined between the first test electrodes. different .

[0107] In such embodiments, the detection assembly further comprises a second test electrode device. The second test electrode device comprises a plurality of second test electrodes. Each of the second test electrodes comprises a second analyte interacting portion configured to selectively interact with a second analyte different from the first analyte. A second saturation limit is defined for each of the second test electrodes, at which point the second analyte interacting portion is saturated with the second analyte. Each second saturation limit is defined between the second test electrodes. different .

[0108] The detection assembly further comprises at least one set of control electrodes providing a set of control electrode regions, each control electrode region configured to provide a control measurement independent of the analyte. Each control electrode region is provided for one of the first test electrodes and / or one of the second test electrodes.

[0109] In a non-limiting embodiment, at least one set of control electrodes comprises a set of first control electrodes and a set of second control electrodes. In such an embodiment, the first set of control electrodes provides a set of first control electrode regions, each of which is provided for one of the first test electrodes, and the second set of control electrodes provides a second set of control electrode regions, each of which is provided for one of the second test electrodes.

[0110] The detection assembly may be configured to detect two, three, four, five, six, or more different analytes. For this purpose, the detection assembly may comprise a second, third, fourth, fifth, sixth, or nth test electrode device and a second, third, fourth, fourth, fifth, sixth, or nth set of control electrodes.

[0111] In non-limiting embodiments, test electrodes such as a first test electrode and a second test electrode, and control electrodes such as a first control electrode and a second control electrode, may be provided on a single substrate, for example, on a single semiconductor substrate. For example, test electrodes such as a first test electrode and a second test electrode, and control electrodes such as a first control electrode and a second control electrode, may be provided on a common slide, chip, or strip. This embodiment is described below herein with reference to Figure 11.

[0112] In the embodiment, each of the multiple analytes is independently selected from molecular species, metal ions, viruses, and microorganisms.

[0113] In non-limiting embodiments, one or more of the analytes are biomarkers such as cytokines or hormones, as they are relevant in the context of patient monitoring and diagnostic testing.

[0114] One or more of the analytes, for example, each may be a hormone selected from eicosanoids, steroids, amino acids, amines, peptides, or proteins.

[0115] In non-limiting embodiments, the analytes, such as the first analyte and the second analyte, may be hormones such as two or more of estradiol (E-2), luteinizing hormone (LH), progesterone, and follicle-stimulating hormone (FSH).

[0116] Aside from being configured to detect different analytes, the first test electrode apparatus and the second test electrode may be as described above in relation to the test electrode apparatus. Similarly, the first and second sets of control electrodes may be as described above in relation to a set of control electrodes.

[0117] Figure 1 provides a schematic plan view of a detection assembly 100 according to an embodiment. The detection assembly 100 comprises a plurality, in this case two, test electrodes 102 and a corresponding number, in this case two, control electrode regions 104.

[0118] In the non-limiting embodiment shown in Figure 1, the test electrode 102 and the control electrode region 104 are provided on a common substrate 106, for example, a silicon substrate 106, which is formed using semiconductor lithography technology.

[0119] The detection assembly 100 shown in Figure 1 comprises a series of, for example, a pair of test electrode-control electrode regions 108A, 108B, and the test electrode 102 is functionalized with a capture species configured to interact with, for example, the analyte, e.g., bind to it. different The region has a capture species, in this case the capture species includes an aptamer. For each pair 108A, 108B, in this non-limiting embodiment the control electrode region 104 is identical to the region of the test electrode 102 functionalized with the capture species.

[0120] As shown in Figure 1, the control electrode region 104 is numbered 1 and 3, and the test electrode 102 is numbered 2 and 4. Figure 2 provides a graph of the sensor signal versus time of the detection assembly 100 shown in Figure 1 when detecting a sample matrix with various analyte concentrations.

[0121] In this non-limiting embodiment, the electroactive portion is contained in a control aptamer (not shown in Figure 1) that functionalizes the surface of each control electrode region 104. The electroactive portion, for example, methylene blue, is positioned proximal to the surface of each control electrode region.

[0122] The sample matrix containing the analyte is introduced at point 110 in Figure 2. Since the analyte does not interact, for example, bind to any of the control electrode regions 104, the signals for control electrode regions 1 and 3 remain substantially unchanged upon addition of the analyte, as shown in the figure. Nevertheless, because control electrode region 3 has a larger area functionalized with the control aptamer than control electrode region 1, the absolute signal for control electrode region 3 is larger.

[0123] Figure 2 provides plots of three sample matrices, each with a different analyte concentration than the other sample matrices. As indicated by arrow 112, the signal to test electrode number 4 decreases as the analyte concentration in each sample matrix increases. This is because the aptamers have electroactive portions that are moved away from the surface of each test electrode 102 by interaction between the analyte and the aptamer, as previously described. As shown in plots 114A, 114B, and 114C, the signal changes with increasing analyte concentration in the sample matrices, indicating that more surface aptamers are binding to the analyte.

[0124] Furthermore, as indicated by arrow 116, the signal to test electrode number 2 decreases as the concentration of the analyte in each sample matrix increases. The sample matrix for plot 118A is identical to that of plot 114A. Similarly, the sample matrices for plots 118B and 118C are identical to those for plots 114B and 114C, respectively.

[0125] Plot 118A indicates that the analyte concentration is such that only a portion of the available aptamers bind to the analyte. Plots 118B and 118C indicate that test electrode number 2 is saturated with the analyte, as the overall signal change is identical despite the sample matrix having a higher analyte concentration compared to plot 118C.

[0126] From the circular ranges 120 and 122 in Figure 2, it is clear that different transient responses to a given analyte concentration can be observed from the lower saturation limit test electrode (number 2) compared to the higher saturation limit test electrode (number 4). In particular, referring to the circular range 122, the overall change in the signal is identical for plots 118B and 118C, but the rate of change in the signal in plot 118B appears to be clearly different from the rate of change in the signal in plot 118C. The rate of change is significantly faster in plot 118C, where the analyte concentration is higher.

[0127] Therefore, a single analyte concentration in the sample matrix can generate multiple signal inputs, namely the absolute change in current between the test electrode-control electrode region and 10⁸A and 10⁸B from a smaller region to a larger region, and different rates of change in current. Such multiple signal inputs can be inversely superimposed and integrated to obtain a specific concentration of the analyte. This technique can improve the accuracy of concentration determination compared to concentrations derived from a single signal input.

[0128] More generally, for example, an electrical signal may be monitored in the time domain to allow for the determination of the rate of signal change.

[0129] The rate of signal change, the absolute value of the signal, and in some embodiments, further signal input may be used to determine the analyte concentration.

[0130] Figure 3 provides a schematic plan view of the array test electrodes 102A, 102B, and 102C in the upper pane. Each conductive region of each test electrode 102A, 102B, and 102C is distinct from the others, as shown. This may allow the use of the same protocol for functionalizing each test electrode. In this regard, the lower pane of Figure 3 shows the same reagent drop size 124 used for each of the test electrodes 102A, 102B, and 102C in the test electrode apparatus. Similarly, the same reagents, washing solutions, etc., may be used for each of the test electrodes 102A, 102B, and 102C. This allows, different A convenient method may be provided to realize test electrodes 102A, 102B, and 102C that have a saturation limit.

[0131] For example, the droplet size 124, which corresponds to the maximum diameter of each droplet on a plane parallel to the surface of the substrate on which the electrode region is provided, can be, for example, 100 μm, or 50 μm to 150 μm, or 10 μm to 150 μm. The electrode region can have a diameter in the range of 1 μm to 100 μm, for example, 10 μm to 100 μm.

[0132] For immobilizing the captured species, a drop of the same size, e.g., 100 μm, can be used, but in this embodiment, the capture / functionalization region is based on the conductive region of the electrode.

[0133] In examples where the control electrode region 104 is surface-functionalized with a control aptamer, it should be noted that control electrode regions 104 of different sizes can be realized in a similar manner using the same reagent drop size, reagents, washing, etc.

[0134] Figure 4 schematically shows analyte detection using the detection assembly 100 according to another embodiment. The detection assembly 100 comprises a plurality, in this case four, test electrodes 102 and a corresponding number, in this case four, control electrode regions 104.

[0135] More generally, it should be noted that any number of test electrodes 102 (and control electrode regions 104), such as two, three, four, five, six, seven, eight, nine, ten, or more, may be intended, for example, according to a desired dynamic range for the sensing assembly 100.

[0136] The detection assembly 100 shown in Figure 4 comprises a series of, for example, a set of, test electrode-control electrode region pairs 108A, 108B, 108C, 108D, and the test electrode 102 is functionalized with a capture species configured to interact with, for example, bind to, the analyte 126. different The region has a capture species, in this case the capture species includes aptamer 128. For each pair 108A, 108B, 108C, and 108D in this non-limiting embodiment, the control electrode region 104 is identical to the region of the test electrode 102 functionalized with the capture species.

[0137] In this non-limiting embodiment, the control aptamer 132 functionalizing the surface of each control electrode region 104 includes an electroactive portion 130. The electroactive portion 130, for example, methylene blue, is positioned in close proximity to the surface of each control electrode region 104.

[0138] As schematically shown in Figure 4, as a result of the conformational change caused by the interaction, for example, binding, of aptamer 128 with analyte 126, the electroactive moiety 134, e.g., methylene blue, contained in aptamer 128 migrates further from the surface of each test electrode 102 than when aptamer 128 does not interact with analyte 126. As shown in Figure 5, a corresponding decrease in the current of each test electrode 102 is observed due to the interaction between analyte 126 and aptamer 128.

[0139] As shown in Figure 4, the control electrode region 104 is numbered 1, 3, 5, and 7, and the test electrode 102 is numbered 2, 4, 6, and 8. Figure 5 provides a graph of the sensor signal versus time for the detection assembly and sample matrix shown in Figure 4, where the concentration of analyte 126 in the sample matrix is ​​relatively high.

[0140] As a result of this relatively high concentration of analyte 126, test electrodes numbered 2, 4, and 6 in Figure 4 become saturated. As shown in Figure 5, in this particular embodiment, the current in each of the test electrodes numbered 2, 4, and 6 decreases and approaches zero current. Test electrode number 8 is not saturated because not all of the aptamers 128 on the surface of this test electrode are interacting with the analyte 126. Therefore, in this case, the current in test electrode number 8 does not decrease to approximately zero current.

[0141] Since the control aptamer 132 does not bind to the analyte 126, there is virtually no change in the current within the control electrode region 104; however, a relatively small signal related to the interaction with the sample matrix is ​​still observed for each of the control electrode regions 104. As shown in Figure 5, as previously described with respect to Figures 1 and 2, the absolute signal increases as the number of control electrode regions increases, and as a result, the largest absolute signal is observed in control electrode region number 7.

[0142] Figure 6 schematically illustrates analyte detection using the detection assembly 100 shown in Figure 4, but with a relatively low concentration of analyte 126 in the sample matrix. Figure 7 provides a graph of the sensor signal versus time for the detection assembly 100 and sample matrix shown in Figure 6. In this case, compared to the relatively high-concentration scenarios in Figures 4 and 5, the current approaches zero at fewer of the test electrodes 102. In particular, only the test electrodes numbered 2 and 4 in Figure 6 saturate to approximately zero current. The test electrodes numbered 6 and 8 do not saturate at this lower analyte 126 concentration and therefore do not decrease to approximately zero current like the test electrodes numbered 2 and 4.

[0143] Figure 8 provides simplified graphs of sensor signals versus time for the higher analyte 126 concentration scenarios in Figures 4 and 5 (left graph) and the lower analyte 126 concentration scenarios in Figures 6 and 7 (right graph).

[0144] As is clear from Figure 8, a higher analyte concentration has the effect of accelerating the signal change and increasing the number of test electrodes 102 where the current decreases to approximately zero. Conversely, a lower analyte concentration slows down the signal change and reduces the number of test electrodes 102 where the current decreases to approximately zero.

[0145] In other words, the absolute decrease in current may depend on the analyte concentration and the saturation limit of the test electrode 102, e.g., the functionalization region / number of immobilized captured species of the test electrode 102. The rate of change of current may also depend on the concentration.

[0146] Therefore, these embodiments point out the absolute change in current within the test electrode-control electrode region from a smaller area to a larger area 108A, 108B, and the different rates of change in current that enable determination of the concentration of analyte 126 by, for example, the inverse superposition integral of such multiple signal inputs as described above.

[0147] A set of control electrodes is shown in Figures 1, 4, and 6 as an array of control electrode regions 104, particularly a linear array, but this is not intended to be limiting. Figure 9 provides a schematic plan view of a set of control electrodes according to an alternative embodiment. In this case, the set of control electrodes comprises a plurality of portions, each individually addressable, for example, conductive portions 138A, 138B, and 138C. Each of the set of control electrode regions 104 can be defined by addressing one or more of the plurality of portions 138A, 138B, and 138C.

[0148] Therefore, for example, the selection of each control electrode area can be made by addressing / activating one of those parts, or a particular combination thereof, via a suitable switching device (not shown in Figure 9). For example, the largest control electrode area may be provided by selecting all three parts 138A, 138B, and 138C, and the smallest control electrode area may be selected by selecting only the smallest part 138A. More generally, as mentioned above, the control electrode area may be selected according to the saturation limit of one of the test electrodes 102.

[0149] As shown in Figure 9, portions 138A, 138B, and 138C may be arranged in the form of concentric or elliptical portions 138A, 138B, and 138C. In other non-limiting embodiments, portions 138A, 138B, and 138C may be arranged in other configurations such as forming an intersection of portions 138A, 138B, and 138C. Such arrangements may help to save space on the substrate where a set of control electrodes are located, for example.

[0150] Figure 9 shows three parts 138A, 138B, and 138C, but this is not intended to be limiting. Any number of parts 138A, 138B, and 138C, such as two, four, five, six, seven, eight, or more, are considered. The number and size of parts 138A, 138B, and 138C may be selected according to, for example, the number and saturation limit of the functionalization regions of the test electrode 102.

[0151] Figure 10 schematically shows a test electrode 102 according to an embodiment in which the captured species are held adjacent to the surface of the test electrode 102 by a film 140. The film 140 allows the analyte to pass through it and thereby be captured by the captured species positioned between the surface of the test electrode 102 and the film 140.

[0152] In such non-limiting embodiments, parameters related to the amount of captured species in each test electrode 102 may include the concentration of captured species in the solution 142 provided between the membrane 140 and the surface of the test electrode 102. For each of the test electrodes 102, the concentration of captured species in the solution 142 is difference By doing so, the saturation limit of the test electrode 102 is difference It can be made to happen.

[0153] In certain non-limiting embodiments, the captured species includes or is defined by glucose oxidase, and the analyte is glucose. Upon passing through the membrane 140, for example, by diffusion, and reaching the solution trapped between the membrane 140 and the test electrode 102, the glucose may be oxidized by glucose oxidase and the oxygen reduced to hydrogen peroxide. The hydrogen peroxide can be electrochemically quantified via reduction to oxygen and hydrogen cations on the surface of the test electrode 102, so that the glucose concentration can be determined accordingly.

[0154] Figure 11 schematically shows an exemplary detection assembly 100 for detecting multiple different analytes. As shown in Figure 11, the detection assembly 100 comprises a first analyte test section 152, a second analyte test section 154, a third analyte test section 156, and a fourth analyte test section 158.

[0155] In the non-limiting embodiment shown in Figure 11, the first to fourth analyte test sections 152 to 158 are conveniently mounted on a common substrate, for example, a common slide / chip / strip. In other embodiments, the analyte test sections 152 to 158 may be mounted on separate substrates.

[0156] The first analyte test section 152 comprises a first test electrode apparatus comprising a plurality of first test electrodes 102. Each of the first test electrodes 102 comprises a first analyte interaction section configured to selectively interact with a first analyte, in this particular case luteinizing hormone (LH). A first saturation limit at which the first analyte interaction section is saturated with the first analyte is defined for each of the first test electrodes 102. The respective first saturation limits are defined between the first test electrodes 102. different .

[0157] The first analyte test section 152 further comprises a first set of control electrodes providing a first set of control electrode regions 104, each first control electrode region 104 configured to provide a control measurement independent of each of the analytes. Each control electrode region 104 is provided for one of the first test electrodes 102.

[0158] The second analyte test section 154 is, different The second test electrode apparatus comprises a plurality of second test electrodes 202 having a saturation limit and configured to selectively interact with a second analyte, in this particular case estradiol (E-2). The second analyte test section 154 also comprises a second set of control electrodes providing a second set of control electrode regions 204, each second control electrode region 204 provided for one of the second test electrodes 202.

[0159] The third analyte test section 156 is, different The third test electrode apparatus comprises a plurality of third test electrodes 302 having a saturation limit and configured to selectively interact with a third analyte, in this particular case, progesterone. The third analyte test section 156 also comprises a third set of control electrodes providing a third set of control electrode regions 304, each third control electrode region 304 provided for one of the third test electrodes 302.

[0160] The fourth analyte test section 158 is, different The fourth test electrode apparatus comprises a plurality of fourth test electrodes 402 having a saturation limit and configured to selectively interact with a fourth analyte, in this particular case, follicle-stimulating hormone (FSH). The fourth analyte test section 158 also comprises a fourth set of control electrodes providing a fourth set of control electrode regions 404, each of which is provided for one of the fourth test electrodes 402.

[0161] Table 1 provides the concentration ranges of first to fourth analytes that can be detected by the detection assembly 100 according to a non-limiting embodiment shown in Figure 11.

[0162] [Table 1]

[0163] The multiple signals generated for each of the first to fourth analytes can be used to determine their concentration, as described above, using a suitable algorithm that takes into account, for example, the absolute change in the signal in the test electrode-control electrode pair and the rate of change in the signal.

[0164] Such a detection assembly 100 may enable, for example, the periodic measurement of the concentrations of multiple analytes, for example, daily. These concentrations can then be tracked and, in some embodiments, uploaded, and individual user profiles may be generated based on the uploaded concentrations. In this way, the concentrations obtained through the detection assembly 100 can be used, for example, for clinical decisions regarding dosage and / or timing of dose administration.

[0165] Figure 12 provides a block diagram of system 500 according to an embodiment. System 500 is for determining the concentration of an analyte in a sample matrix. System 500 comprises a detection assembly 100 for detecting the analyte. The detection assembly 100 comprises a test electrode device 502. The test electrode device 502 comprises a plurality of test electrodes 102. Each of the test electrodes 102 has an analyte interaction portion configured to selectively interact with the analyte. A saturation limit is defined for each of the test electrodes 102 at which the analyte interaction portion is saturated with the analyte. The respective saturation limits are defined between the test electrodes 102. different The detection assembly 100 further comprises a pair of control electrodes 504 that provide a pair of control electrode regions 104, each control electrode region 104 provided for one of the test electrodes 102.

[0166] Therefore, the sensing assembly 100 included in the system 500 may conform to any of the examples and embodiments described herein.

[0167] The system 500 also includes a signal processing unit 506 and a concentration determination unit 508. The signal processing unit 506 is configured to process signals received from multiple test electrodes 102 and signals received from a set of control electrode regions 104. The concentration determination unit 508 is configured to determine the concentration of the analyte in the sample matrix based on the signals processed from the multiple test electrodes 102 and the signals processed from the set of control electrode regions 104.

[0168] In at least some embodiments, the concentration determination unit 508 is configured to determine the concentration based on one or more differential signals from signals processed from a plurality of test electrodes 102 and signals processed from a set of control electrode regions 104.

[0169] In non-limiting embodiments, the concentration determination unit 508 is configured to determine the concentration based on the absolute amount of change in the signal and the rate of change in the signal at the test electrode-control electrode pairs 108A, 108B, 108C, and 108D.

[0170] Although not visible in Figure 12, the system 500 may include a user interface, such as a display, for communicating the analyte concentration determined by the concentration determination unit 508. Alternatively or additionally, the system 500 may include a transmitter (not visible in Figure 12), such as a wireless transmitter, configured to transmit the analyte concentration determined by the concentration determination unit 508 to an external device such as a personal computer, tablet, smartphone, or remote server.

[0171] Figure 13 shows a flowchart of Method 600 according to an embodiment. Method 600 is for determining the concentration of an analyte in a sample matrix. The method includes processing signals received from a plurality of test electrodes in block 602. Each test electrode comprises an analyte interaction portion configured to selectively interact with the analyte. A saturation limit at which the analyte interaction portion is saturated with the analyte is defined for each test electrode, and the respective saturation limits are between the test electrodes. different .

[0172] Method 600 also includes processing signals received from a set of control electrodes in block 604. The set of control electrodes provides a set of control electrode regions, each control electrode region is configured to provide a control measurement independent of the analyte, and each control electrode region is provided for one of the test electrodes.

[0173] In block 606, the concentration of the analyte in the sample matrix is ​​determined based on signals processed from multiple test electrodes and signals processed from a set of control electrodes.

[0174] In some embodiments, determining the concentration of the analyte (606) includes determining one or more differential signals from signals processed from a plurality of test electrodes and signals processed from a set of control electrodes.

[0175] In non-limiting embodiments, the determination 606 is based on the absolute change in the signal and the rate of change in the test electrode-control electrode pair.

[0176] Method 600 may employ the detection assembly 100 and / or system 500, for example, according to any of the embodiments and examples described herein.

[0177] In particular, method 600 may be implemented using the signal processing unit 506 and the concentration determination unit 508 of the system 500 of the present disclosure.

[0178] In certain embodiments, a computer program, including computer program code, is adapted to implement method 600 according to any of the embodiments and examples described herein when the program is executed on a computer. Such a computer may be included in, or defined, the signal processing unit 506 and the concentration determination unit 508 of the system 500 of the present disclosure. The computer program may be stored in one or more non-temporary computer-readable media. The computer program may include instructions that can cause one or more processors, which are executed by one or more physical computing devices such as one or more processors, to implement, execute, and / or perform one or more methods described herein.

[0179] More generally, the examples and embodiments described herein with respect to the sensing assembly 100 may be applicable to the system 500, method 600, and / or computer program. Similarly, the examples and embodiments described herein with respect to the system 500, method 600, and / or computer program may be applicable to the sensing assembly 100.

[0180] Figure 14 provides a diagram of a test electrode apparatus 502 according to a non-limiting embodiment. The depicted test electrode apparatus 502 comprises several units 702A, 702B, and 702C, each unit 702A, 702B, and 702C defining one of the test electrodes and comprising several test electrode subunits 703. The number of test electrode subunits 703 in each unit 702A, 702B, and 702C determines, at least in part, the saturation limit of each test electrode.

[0181] If each unit 702B, 702C includes two or more test electrode subunits 703, the test electrode subunits 703 of each unit 702B, 702C can be connected to each other, as shown in Figure 14.

[0182] In the embodiment shown in Figure 14, units 702A, 702B, and 702C are mounted on a common substrate 106. Nevertheless, it should be noted that in other embodiments, at least some of units 702A, 702B, and 702C may be mounted on a substrate different from the other units 702A, 702B, and 702C.

[0183] In the embodiment shown in Figure 14, the test electrode subunits 703 are arranged linearly with respect to each unit 702A, 702B, and 702C. For example, when a reagent is dropped onto two or more of the test electrode subunits 703 simultaneously, this spatial arrangement can easily functionalize the test electrode subunits 703. Nevertheless, alternative spatial arrangements of the test electrode subunits 703 can be considered, for example, to save space on the substrate 106.

[0184] As shown in Figure 14, unit 702A has one test electrode subunit 703, unit 702B has two test electrode subunits 703, and unit 702C has four test electrode subunits 703. More generally, the saturation limits of units 702A, 702B, and 702C can be determined without necessarily requiring different functionalization protocols / reagents used to prepare each unit 702A, 702B, and 702C. difference To enable this, any number of test electrode subunits 703 can be intended for each unit 702A, 702B, and 702C.

[0185] In the non-limiting embodiment shown in Figure 14, each test electrode subunit 703 has the same area as the others. This makes it possible, for example, to use the same reagent drop size, reagents, and washing for each of these test electrode subunits 703.

[0186] In this regard, Figure 15 schematically shows an exemplary functionalization process in which the same reagent drop size 124 is used for each of the test electrode subunits 703. different This may provide a convenient method for realizing units 702A, 702B, and 702C that have a saturation limit.

[0187] The droplet size 124, for example, the maximum diameter of each droplet in a plane parallel to the surface of the substrate 106, can be between 10 μm and 150 μm, such as 100 μm. The area of ​​each test electrode subunit 703 can be in the range of 1 μm to 100 μm, such as 10 μm to 100 μm.

[0188] More generally, at least some of units 702A, 702B, and 702C are such that each of units 702A, 702B, and 702C is such that different It may have a subunit 703 designed to have overlapping analyte depletion diffusion / material transport regions so that it can function as a single, larger test electrode with transient response.

[0189] Alternatively or additionally, at least some of units 702A, 702B, and 702C may have subunits 703 that are physically separated from each other within each unit 702A, 702B, and 702C, so as not to have overlapping analyte depletion diffusion / material transport regions. Each of such units 702A, 702B, and 702C may act as a larger region electrode with a relatively constant transient response.

[0190] Figures 16 to 18 schematically show exemplary sensing assemblies 100, each including a capacitance and / or impedance determination assembly.

[0191] Such capacitance and / or impedance determination assemblies may include a further electrode device 802A, and at least some of the test electrodes 802B of the test electrode device may be spaced apart from the further electrode device so that the capacitance and / or impedance between at least some of the test electrodes 802B and the further electrode device 802A can be determined. The test electrodes are as described above, different Saturation limit.

[0192] At least some of the further electrode devices 802A and test electrodes 802B may be arranged relative to each other in any preferred manner, such as using the cross arrangement schematically shown in Figure 16.

[0193] As shown in Figure 16, further electrode devices 802A may extend from the first contact 803A, and at least some of the test electrodes 802B may extend from the second contact 803B. In this non-limiting embodiment, the first and second contacts 803A, 803B, and the electrode devices 802A, 802B are arranged on a common substrate 106, such as a common semiconductor substrate.

[0194] In the non-limiting embodiment shown in Figure 16, the further electrode apparatus 802A itself comprises one or more of the test electrodes, and as a result, each of the intersecting “plates” of spatially separated capacitance and / or impedance determination assemblies comprises an analyte interaction portion, for example, in the form of a surface functionalized with the capture species described above.

[0195] In the embodiment shown in Figure 17, which illustrates a partial cross-section of the capacitance and / or impedance determination assembly, both electrode devices 802A and 802B are raised from the surface of the substrate 106. Therefore, an electric field is provided on the surface of the substrate 106, and the electric field line 805 extends above the gap between the electrode devices 802A and 802B.

[0196] In an alternative, non-limiting embodiment shown in Figure 18, a trench 807 is provided between the electrode devices 802A and 802B. In this embodiment, the electrode devices 802A and 802B, for example, the mating electrode devices 802A and 802B, may be set within the substrate 106 as shown.

[0197] While exemplary embodiments of the apparatus, system, and method are provided, please understand that the detailed description and specific examples are for illustrative purposes only and are not intended to limit the scope. These and other features, aspects, and advantages of the apparatus, system, and method of the present invention can be better understood from the description, the appended claims, and the appended drawings. Please understand that the drawings are schematic diagrams only and are not drawn to scale. Also understand that the same reference numerals are used throughout the drawings to indicate identical or similar parts.

[0198] Other modifications of embodiments of the present disclosure can be understood and implemented by a person skilled in the art by working the present disclosure, based on a study of the drawings, the present disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite articles “a” or “an” do not exclude plurals. The mere fact that certain measures are described in different dependent claims does not imply that combinations of these measures cannot be used to one's advantage. No reference numeral in the claims should be construed as limiting the scope.

Claims

1. A detection assembly for detecting an analyte, wherein the detection assembly is A test electrode apparatus comprising multiple test electrodes, wherein each test electrode comprises an analyte interaction portion configured to selectively interact with the analyte, and a saturation limit at which the analyte interaction portion is saturated with the analyte is defined for each test electrode, and the respective saturation limits differ among the test electrodes. A set of control electrodes providing a set of control electrode regions, each control electrode region configured to provide a control measurement value independent of the analyte, and each control electrode region provided for one of the test electrodes, Equipped with, The test electrode apparatus and the set of control electrodes are arranged to receive a sample matrix suitable for containing the analyte. The detection assembly comprises an electrochemical cell including a working electrode assembly and a counter electrode, the working electrode assembly comprises the test electrode device, and the test electrode device is configured to determine a change in current associated with selective interaction with the analyte. A sensing assembly comprising the working electrode assembly, the set of control electrodes, the set of control electrodes configured to determine a change in current associated with the sample matrix in contact with the control electrode region.

2. The detection assembly according to claim 1, wherein the control electrode regions are relatively different from each other.

3. The detection assembly according to claim 2, wherein the differences in the control electrode regions allow for ordering the control electrode regions by increasing their size, the differences in the saturation limits allow for further ordering of the test electrodes by increasing the saturation limits, and a series of test electrode-control electrode region pairs are defined according to the ordering and further ordering such that the smallest control electrode region is paired with the test electrode having the smallest saturation limit, and the largest control electrode region is paired with the test electrode having the largest saturation limit.

4. The detection assembly according to claim 3, wherein, with respect to a series of pairs of test electrode-control electrode regions, an incremental change in the control electrode region corresponds to a further incremental change in the saturation limit of the test electrode.

5. The detection assembly according to any one of claims 1 to 4, wherein each analyte interaction portion is defined by a capture species provided adjacent to the surface of each of the test electrodes, and the capture species is configured to selectively interact with the analyte.

6. The detection assembly according to claim 5, wherein the captured species comprises at least one selected from proteins, peptides, carbohydrates, and nucleic acids.

7. The detection assembly according to claim 6, wherein the protein is an enzyme.

8. The detection assembly according to any one of claims 5 to 7, wherein the captured species includes an aptamer.

9. The detection assembly according to any one of claims 5 to 8, wherein the surface is functionalized with the capture species.

10. The detection assembly according to any one of claims 5 to 8, wherein the captured species is held adjacent to the surface by a membrane.

11. The detection assembly according to any one of claims 5 to 10, wherein a parameter relating to the amount of the captured species for each of the test electrodes at least partially determines the saturation limit of each of the test electrodes.

12. The detection assembly according to claim 9, wherein a parameter relating to the amount of the captured species for each of the test electrodes at least partially determines the saturation limit of each of the test electrodes, and the parameter includes at least one of the area of ​​the surface functionalized with the captured species and the density of the captured species on the surface.

13. The detection assembly according to claim 12, wherein each control electrode region corresponds to the area of ​​the surface of one of the test electrodes functionalized with the capture species.

14. The detection assembly according to claim 10, wherein a parameter relating to the amount of the captured species for each of the test electrodes at least partially determines the saturation limit of each of the test electrodes, and the parameter includes the concentration of the captured species in a solution provided between the membrane and the surface.

15. The detection assembly according to any one of claims 1 to 14, wherein each of the set of control electrodes comprises a plurality of individually addressable portions, and each of the set of control electrode regions is defined by addressing one or more of the plurality of portions.

16. The detection assembly according to any one of claims 1 to 15, wherein the test electrode device comprises a plurality of units, each unit defining one of the test electrodes and comprising a plurality of test electrode subunits, the number of test electrode subunits in each unit at least partially determining the saturation limit of each of the test electrodes.

17. The detection assembly according to any one of claims 1 to 16, wherein the control electrode region is configured for non-selective interaction with the sample matrix.

18. The detection assembly according to any one of claims 1 to 16, wherein the control electrode region is configured to selectively interact with non-analytes contained in the sample matrix.

19. The detection assembly according to any one of claims 1 to 18, wherein the electrochemical cell further comprises a reference electrode.

20. The detection assembly according to any one of claims 1 to 19, comprising a capacitance and / or impedance determination assembly equipped with the test electrode device.

21. The detection assembly according to claim 20, wherein the capacitance and / or impedance determination assembly comprises a further electrode device, and at least some of the test electrodes of the test electrode device are spaced apart from the further electrode device so as to be able to determine the capacitance and / or impedance between at least some of the test electrode device and the further electrode device.

22. The detection assembly according to claim 21, wherein the capacitance and / or impedance determination assembly further comprises a set of control electrodes, the set of control electrodes being spaced apart from the further electrode device so as to be able to determine the capacitance and / or impedance between the set of control electrodes and the further electrode device.

23. A detection assembly for detecting multiple mutually different analytes, wherein the detection assembly is A first test electrode apparatus comprising a plurality of first test electrodes, each of the first test electrodes comprising a first analyte interaction portion configured to selectively interact with a first analyte, wherein a first saturation limit is defined for each of the first test electrodes at which the first analyte interaction portion is saturated with the first analyte, and the respective first saturation limits differ among the first test electrodes. A second test electrode apparatus comprising a plurality of second test electrodes, wherein each of the second test electrodes comprises a second analyte interaction portion configured to selectively interact with a second analyte different from the first analyte, and a second saturation limit is defined for each of the second test electrodes at which the second analyte interaction portion is saturated with the second analyte, and the respective second saturation limits differ among the second test electrodes. A set of control electrodes providing a set of control electrode regions, each control electrode region configured to provide a control measurement value independent of the analyte, and each control electrode region provided for one of the first test electrode and / or the second test electrode, A detection assembly comprising:

24. A system for determining the concentration of an analyte in a sample matrix, A detection assembly according to any one of claims 1 to 23, A signal processing unit, To process the signals received from the plurality of test electrodes, and A signal processing unit configured to process signals received from the aforementioned set of control electrode regions, A concentration determination unit configured to determine the concentration of the analyte in the sample matrix based on the signals processed from the plurality of test electrodes and the signals processed from the set of control electrode regions, A system equipped with these features.

25. The system according to claim 24, wherein the concentration determination unit is configured to determine the concentration based on one or more differential signals between the signals processed from the plurality of test electrodes and the signals processed from the set of control electrode regions.

26. The system according to claim 24 or 25, wherein the concentration determination unit is configured to determine the concentration based on the absolute amount of change of the processed signal from the test electrode and the set of control electrode regions and the rate of change of the processed signal from the plurality of test electrodes.

27. A method for determining the concentration of an analyte in a sample matrix, Processing signals received from multiple test electrodes, wherein each test electrode comprises an analyte interaction portion configured to selectively interact with the analyte, and a saturation limit at which the analyte interaction portion is saturated with the analyte is defined for each test electrode, and the respective saturation limits differ among the test electrodes. Processing signals received from a set of control electrodes, wherein the set of control electrodes provides a set of control electrode regions, each control electrode region is configured to provide a control measurement value independent of the analyte, and each control electrode region is provided for one of the test electrodes. The plurality of test electrodes are included in a test electrode device, and the test electrode device and the set of control electrodes are arranged to receive the sample matrix. The test electrode device and the set of control electrodes are included in a detection assembly, the detection assembly comprising an electrochemical cell including a working electrode assembly and a counter electrode, the working electrode assembly comprising the test electrode device, the test electrode device being configured to determine a change in current associated with selective interaction with the analyte, The working electrode assembly comprises a set of control electrodes, the set of control electrodes configured to determine a change in current associated with the sample matrix in contact with the control electrode region, and the process involves: The concentration of the analyte in the sample matrix is ​​determined based on the signals processed from the plurality of test electrodes and the signals processed from the set of control electrode regions. Methods that include...

28. The method according to claim 27, wherein determining the concentration of the analyte includes determining one or more differential signals from the signals processed from the plurality of test electrodes and the signals processed from the set of control electrode regions.

29. The method according to claim 27 or 28, wherein determining the concentration of the analyte is based on the absolute change in the processed signal from the test electrode and the set of control electrode regions and the rate of change in the processed signal from the plurality of test electrodes.

30. A computer program including computer program code, wherein when the computer program is executed on one or more physical computing devices, it is configured to cause one or more physical computing devices to implement the method according to any one of claims 27 to 29.

31. One or more non-temporary computer-readable media storing a computer program, wherein the computer program includes computer program code, and the non-temporary computer-readable media are configured such that when the computer program is executed on one or more physical computing devices, the one or more physical computing devices implement the method according to any one of claims 27 to 29.

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