A highly monochromatic electrochemiluminescence system with radiation band in blue-green region and construction method

Abstract

The application relates to a highly monochromatic electrochemiluminescence system and a construction method of the system, wherein Hepes is used as a buffer solution, hydrazine hydrate is used as a co-reagent, Zn 2+ The highly monochromatic electrochemiluminescence system is composed of aggregation-induced gold nanoclusters as a luminescent reagent. The maximum emission wavelength of the system is 485nm, and the half-peak width is 36nm. The electrochemiluminescence characteristic emission range of the nanomaterials is effectively widened, and the types of the highly monochromatic electrochemiluminescence system are enriched.

Description

TECHNICAL FIELD

[0001] The present application relates to a highly monochromatic electrochemiluminescence system and a construction method thereof, and belongs to the technical field of electrochemiluminescence. BACKGROUND

[0002] In the era of Roche's monopoly on electrochemiluminescence in vitro diagnostic applications, the construction of a new type of electrochemiluminescence system using nanoparticles as a luminescent reagent began in 2002 (Science, 2002, 296, 1293), and has been a hot research field in electrochemiluminescence. As of now, the maximum emission wavelength of conventional nanoparticle electrochemiluminescence is usually greater than 500 nm, and the monochromaticity is poor, so it is of great academic and application value to develop a highly monochromatic (half-peak width less than 40 nm) electrochemiluminescence system in the short-wave region (maximum emission wavelength less than 500 nm).

[0003] Recent literature reports show that perovskite nanomaterials can produce electrochemiluminescence with a characteristic emission wavelength of 535 nm and a half-peak width of 25 nm in an organic phase medium (J. Am. Chem. Soc. 2017, 139, 8772), and 6-azido-2-thiothymine-coated Au nanoclusters can produce electrochemiluminescence with a characteristic emission wavelength of 532 nm and a half-peak width of 36 nm in an aqueous medium, and its radiation can be enhanced based on the formation of a hydrogen-bonded rigid host-guest material (Angew. Chem. Int. Edit. 2019, 58, 6901). However, perovskite nanomaterials are ionic crystals and are unstable in water, and 6-azido-2-thiothymine-coated Au nanoclusters cannot be further grafted with biomolecules, so these two types of reagents are difficult to effectively construct a highly monochromatic electrochemiluminescence system suitable for biochemical analysis.

[0004] After searching, there is currently no report on a highly monochromatic electrochemiluminescence system with a maximum emission wavelength of less than 500 nm and suitable for biochemical analysis. SUMMARY

[0005] In view of the deficiencies of the prior art, especially the difficulty of developing a highly monochromatic electrochemiluminescence system with a maximum emission wavelength of less than 500 nm and suitable for biochemical analysis, the present application provides a highly monochromatic electrochemiluminescence system and a construction method thereof, with a radiation wavelength in the blue-green light region.

[0006] The electrochemiluminescence system of the present application uses Zn 2+ The aggregation-induced water-stable gold nanoclusters are used as a luminescent substance, hydrazine hydrate is used as a co-reactant, and Hepes solution is used as a buffer solution, which can realize highly monochromatic electrochemiluminescence radiation in the blue-green light region, with a half-peak width of 36 nm and a maximum emission wavelength of 485 nm.

[0007] The highly monochromatic electrochemiluminescence system with the radiation wave band in the blue-green light region not only widens the electrochemiluminescence characteristic emission range of the nanomaterial, but also is stable in water phase, easy to mark biomolecules, and has wide application prospects in the field of biochemical analysis and detection.

[0008] Term explanation:

[0009] Room temperature: The room temperature has the conventional meaning, and the temperature range is 25±5℃.

[0010] To achieve the above object, the application is realized by the following technical scheme:

[0011] A highly monochromatic electrochemiluminescence system with the radiation wave band in the blue-green light region, which adopts Zn 2+ The highly monochromatic electrochemiluminescence system is composed of the aggregation-induced nanogold cluster as a luminescent reagent, hydrazine hydrate as a co-reagent, and Hepes as a buffer solution.

[0012] According to the application, the pH of the Hepes buffer solution is 7.0-7.4, preferably, the pH of the Hepes buffer solution is 7.2-7.4, and most preferably, the pH of the Hepes buffer solution is 7.4.

[0013] According to the application, in the electrochemiluminescence system, the molar concentration of the Hepes buffer solution is 5-50mM, preferably, the molar concentration of the Hepes buffer solution is 5-20mM, and most preferably, the molar concentration of the Hepes buffer solution is 10mM.

[0014] According to the application, in the electrochemiluminescence system, the molar concentration of the hydrazine hydrate is 1-30mM, preferably, the molar concentration of the hydrazine hydrate is 5-20mM, and most preferably, the molar concentration of the hydrazine hydrate is 10mM.

[0015] According to the application, in the electrochemiluminescence system, the Zn 2+ The characteristic emission wavelength of the aggregation-induced nanogold cluster is 485nm, the half-peak width is 25nm, the ultraviolet absorption characteristic peak is 355nm and 450nm, and the fluorescence lifetime is 31ns.

[0016] According to the application, in the electrochemiluminescence system, the Zn 2+ The mass concentration of the aggregation-induced nanogold cluster is 0.05-0.5mg / mL, preferably, the mass concentration of the Zn 2+ The mass concentration of the aggregation-induced nanogold cluster is 0.10-0.25mg / mL, and most preferably, the mass concentration of the Zn 2+ The mass concentration of the aggregation-induced nanogold cluster is 0.15mg / mL.

[0017] According to a preferred embodiment of the present invention, the Zn 2+ Aggregation-induced gold nanoclusters were prepared by the following method:

[0018] Zn was prepared by reacting chloroauric acid as the gold source, mercaptopropionic acid as the stabilizer, and zinc acetate as the aggregation inducer. 2+ Aggregation-induced gold nanoclusters;

[0019] Preferably, the molar ratio of chloroauric acid to mercaptopropionic acid is 1:32, and the molar ratio of chloroauric acid to zinc acetate is 1:41; the reaction temperature is room temperature, and the reaction time is 6 hours; after the reaction is complete, the product is purified by washing with isopropanol, and then dissolved in deionized water to obtain Zn. 2+ Aggregation-induced gold nanoclusters.

[0020] A preferred embodiment of the present invention:

[0021] Highly monochromatic Zn 2+ The preparation method of aggregation-induced gold nanoclusters includes the following steps:

[0022] (1) Take 35.5 μL of 100 mg / mL HAuCl4·3H2O and add 2.5 mL of deionized water;

[0023] (2) Add 50 μL of mercaptopropionic acid to step (1) and stir for 15 min;

[0024] (3) Add 430 μL of 1M sodium hydroxide to step (2) and adjust the pH to 8.5;

[0025] (4) Add 0.5 mL of 0.1 M zinc acetate to step (3), stir the mixture at room temperature for 6 h. After the reaction is complete, wash the product with isopropanol and then dissolve it in deionized water to obtain Zn. 2+ Monodisperse solution of aggregation-induced gold nanoclusters.

[0026] A method for constructing a highly monochromatic electrochemiluminescence system with radiation band located in the blue-green light region, comprising the following steps:

[0027] Using Hepes as a buffer solution and hydrazine hydrate as a co-reactant, Zn 2+ Aggregation-induced gold nanoclusters were used as luminescent reagents to form an electrochemiluminescence system, which was driven by a three-electrode system and cyclic voltammetry.

[0028] According to a preferred embodiment of the present invention, the electrochemical conditions employed are as follows: using a gold electrode as the working electrode, a platinum wire as the counter electrode, and an Ag / AgCl electrode as the reference electrode, a cyclic voltammetric scan is performed on a monodisperse solution containing a buffer solution, a co-reactant, and a luminescent reagent.

[0029] According to the application, preferably, when performing cyclic voltammetry scanning, the scanning voltage range is 0-1.6V, the scanning circle number is 1-3, and the scanning speed is 40-60mV / s.

[0030] Zn 2+ The aggregation-induced nanometer gold cluster is used as a luminescent reagent, and the luminescent reagent can generate highly monochromatic electrochemiluminescence radiation with a maximum emission wavelength of 485nm in a Hepes buffer containing hydrazine hydrate and driven by potential scanning, and the half peak width is 36nm. After numerous experiments, it is verified that the ECL radiation can be selectively generated only based on a specific co-reactant and buffer. The buffer used is a Hepes buffer, and other buffers cannot generate highly monochromatic characteristic radiation; the co-reactant used is hydrazine hydrate, and other co-reactants cannot generate highly monochromatic characteristic radiation.

[0031] Technical features and advantages of the application:

[0032] 1. The electrochemiluminescence system of the application uses Zn 2+ The aggregation-induced nanometer gold cluster is used as a luminescent reagent, and the luminescent reagent can generate highly monochromatic electrochemiluminescence radiation with a maximum emission wavelength of 485nm in a Hepes buffer containing hydrazine hydrate and driven by potential scanning, and the half peak width is 36nm. After numerous experiments, it is verified that the ECL radiation can be selectively generated only based on a specific co-reactant and buffer. The buffer used is a Hepes buffer, and other buffers cannot generate highly monochromatic characteristic radiation; the co-reactant used is hydrazine hydrate, and other co-reactants cannot generate highly monochromatic characteristic radiation. 2+ The aggregation-induced nanometer gold cluster is water-stable, and Zn 2+ The aggregation-induced nanometer gold cluster / hydrazine hydrate system can generate electrochemiluminescence with a maximum emission wavelength of 485nm in a Hepes buffer based on cyclic voltammetry scanning driving mode, and the half peak width is 36nm, which effectively widens the electrochemiluminescence characteristic emission range of nanometer materials and enriches the types of highly monochromatic electrochemiluminescence systems.

[0033] 2. The Zn 2+ The aggregation-induced nanometer gold cluster / hydrazine hydrate system has highly monochromatic electrochemiluminescence radiation with a maximum radiation wavelength of less than 500nm and is water-stable, which not only effectively avoids the limitation that the perovskite highly monochromatic electrochemiluminescence system cannot be applied to water phase systems, but also breaks through the limitation that existing gold nanoclusters need to rely on hetero nitrogen ligands to implement highly monochromatic ECL.

[0034] 3. The highly monochromatic electrochemiluminescence system of the application in the blue-green light region uses the aggregation-induced nanometer gold cluster as a luminescent reagent. 2+ The aggregation-induced nanometer gold cluster has sufficient carboxyl groups to implement biological labeling and is suitable for further research and development of highly monochromatic electrochemiluminescence biochemical analysis technology. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The UV absorption and photoluminescence diagram of the Zn 2+ The UV absorption and photoluminescence diagram of the Zn

[0036] Figure 2 Zn prepared for Example 1 2+ Fluorescence lifetime profile of aggregation-induced gold nanoclusters; abscissa is time, ordinate is fluorescence intensity.

[0037] Figure 3 Zn prepared for Example 1 2+ Transmission electron micrograph of aggregation-induced gold nanoclusters.

[0038] Figure 4 Zn prepared for Example 1 2+ Elemental mapping of aggregation-induced gold nanoclusters; abscissa is energy, ordinate is number of photons.

[0039] Figure 5 Zn prepared for Example 1 2+ Infrared spectrum of aggregation-induced gold nanoclusters; abscissa is wave number, ordinate is transmittance.

[0040] Figure 6 Zn prepared for Example 1 2+ Photoluminescence profile of aggregation-induced gold nanoclusters after 2 months of storage; abscissa is wavelength, ordinate is fluorescence intensity.

[0041] Figure 7 Zn prepared for Example 1 2+ Photoluminescence profile of aggregation-induced gold nanoclusters after 4 months of storage; abscissa is wavelength, ordinate is fluorescence intensity.

[0042] Figure 8 Zn prepared for Example 1 2+ Photoluminescence profile of aggregation-induced gold nanoclusters after 6 months of storage; abscissa is wavelength, ordinate is fluorescence intensity.

[0043] Figure 9 Cyclic voltammetry driven electrochemiluminescence intensity-potential (time) profile of the luminescent system in Example 2; the luminescent system is 0.15 mg / mL Zn 2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 10 mM Hepes pH = 7.4; potential window is 0-1.6 volts, scan rate is 50 millivolts / second; abscissa is potential, ordinate is electrochemiluminescence intensity.

[0044] Figure 10 Cyclic voltammetry driven electrochemiluminescence spectrum of the luminescent system in Example 2;

[0045] The luminescent system is 0.15 mg / mL Zn 2+Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 10 mM Hepes pH = 7.4; potential window 0-1.6 volts, scan rate 50 mV / s; abscissa wavelength, ordinate electrochemiluminescence intensity.

[0046] Figure 11 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 3;

[0047] The luminescent system was 0.15 mg / mL Zn 2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 5 mM Hepes pH = 7.4; potential window 0-1.6 volts, scan rate 50 mV / s; abscissa wavelength, ordinate electrochemiluminescence intensity.

[0048] Figure 12 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 3;

[0049] The luminescent system was 0.15 mg / mL Zn 2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 15 mM Hepes pH = 7.4; potential window 0-1.6 volts, scan rate 50 mV / s; abscissa wavelength, ordinate electrochemiluminescence intensity.

[0050] Figure 13 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 3;

[0051] The luminescent system was 0.15 mg / mL Zn 2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 20 mM Hepes pH = 7.4; potential window 0-1.6 volts, scan rate 50 mV / s; abscissa wavelength, ordinate electrochemiluminescence intensity.

[0052] Figure 14 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 4;

[0053] The luminescent system was 0.15 mg / mL Zn 2+ Aggregation-induced gold nanoclusters, 5 mM hydrazine hydrate, 10 mM Hepes pH = 7.4; potential window 0-1.6 volts, scan rate 50 mV / s; abscissa wavelength, ordinate electrochemiluminescence intensity.

[0054] Figure 15 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 4;

[0055] The luminescent system was 0.15 mg / mL Zn 2+Aggregation-Induced Gold Nanoclusters, 15 mM Hydrazine hydrate, 10 mM Hepes pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0056] Figure 16 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 4;

[0057] The luminescent system was 0.15 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 20 mM Hydrazine hydrate, 10 mM Hepes pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0058] Figure 17 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 5;

[0059] The luminescent system was 0.10 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Hepes pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0060] Figure 18 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 5;

[0061] The luminescent system was 0.20 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Hepes pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0062] Figure 19 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 5;

[0063] The luminescent system was 0.25 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Hepes pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0064] Figure 20 Cyclic voltammetry driven electrochemiluminescence spectra for the luminescent system in Example 6;

[0065] The luminescent system was 0.15 mg / mL Zn after 2 months2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, and 10 mM Hepes at pH 7.4 were used. The potential window ranged from 0 to 1.6 V, and the scan rate was 50 mV / s. The horizontal axis represents wavelength, and the vertical axis represents electrochemiluminescence intensity.

[0066] Figure 21 The electrochemiluminescence spectrum of the luminescent system in Example 6 is driven by cyclic voltammetry.

[0067] The luminescent system was 0.15 mg / mL Zn after 4 months of storage. 2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, and 10 mM Hepes at pH 7.4 were used. The potential window ranged from 0 to 1.6 V, and the scan rate was 50 mV / s. The horizontal axis represents wavelength, and the vertical axis represents electrochemiluminescence intensity.

[0068] Figure 22 This is the electrochemiluminescence spectrum driven by cyclic voltammetry of the luminescent system in Example 6;

[0069] The luminescent system was 0.15 mg / mL Zn after 6 months of storage. 2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, and 10 mM Hepes at pH 7.4 were used. The potential window ranged from 0 to 1.6 V, and the scan rate was 50 mV / s. The horizontal axis represents wavelength, and the vertical axis represents electrochemiluminescence intensity.

[0070] Figure 23 The electrochemiluminescence spectrum of the luminescent system in Comparative Example 1 is driven by cyclic voltammetry.

[0071] The luminescent system consisted of 10 mM hydrazine hydrate and 10 mM Hepes at pH 7.4; the potential window was 0–1.6 V, and the scan rate was 50 mV / s; the horizontal axis represented wavelength, and the vertical axis represented electrochemiluminescence intensity.

[0072] Figure 24 The electrochemiluminescence spectrum driven by cyclic voltammetry of the luminescent system in Comparative Example 2 is shown.

[0073] The luminescent system was 0.15 mg / mL Zn. 2+ Aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 10 mM pH 9.4 carbonate buffer; potential window 0–1.6 V, scan rate 50 mV / s; x-axis is wavelength, y-axis is electrochemiluminescence intensity.

[0074] Figure 25 The electrochemiluminescence spectrum driven by cyclic voltammetry of the luminescent system in Comparative Example 2 is shown.

[0075] The luminescent system was 0.15 mg / mL Zn. 2+Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Phosphate buffer pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0076] Figure 26 Cyclic voltammetry driven electrochemiluminescence spectra of the light emitting system in Comparative Example 2;

[0077] The light emitting system was 0.15 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Phosphate buffer pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0078] Figure 27 Cyclic voltammetry driven electrochemiluminescence spectra of the light emitting system in Comparative Example 2;

[0079] The light emitting system was 0.15 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Phosphate buffer pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0080] Figure 28 Cyclic voltammetry driven electrochemiluminescence spectra of the light emitting system in Comparative Example 2;

[0081] The light emitting system was 0.15 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Phosphate buffer pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0082] Figure 29 Cyclic voltammetry driven electrochemiluminescence spectra of the light emitting system in Comparative Example 2;

[0083] The light emitting system was 0.15 mg / mL Zn 2+ Aggregation-Induced Gold Nanoclusters, 10 mM Hydrazine hydrate, 10 mM Phosphate buffer pH = 7.4; Potential window 0-1.6 volts, scan rate 50 mV / s; Abscissa wavelength, ordinate electrochemiluminescence intensity.

[0084] Figure 30 Cyclic voltammetry driven electrochemiluminescence spectra of the light emitting system in Comparative Example 2;

[0085] The light emitting system was 0.15 mg / mL Zn2+ Aggregation-induced gold nanoclusters, 10 mM triethanolamine, 10 mM Hepes pH = 7.4; potential window is 0-1.6 volt, scan rate is 50 mV / s; abscissa is wavelength, ordinate is electrochemiluminescence intensity.

[0086] Figure 31 Cyclic voltammetry-driven electrochemiluminescence spectrum of the luminescent system in Comparative Example 3;

[0087] The luminescent system is 0.15 mg / mL Zn 2+ Aggregation-induced gold nanoclusters, 10 mM triethanolamine, 10 mM Hepes pH = 7.4; potential window is 0-1.6 volt, scan rate is 50 mV / s; abscissa is wavelength, ordinate is electrochemiluminescence intensity. DETAILED DESCRIPTION

[0088] The present application is further illustrated by the following examples, but is not limited thereto.

[0089] Zn 2+ The electrochemiluminescence-potential curve of the aggregation-induced gold nanoclusters was obtained by an MPI-II electrochemiluminescence analyzer of Xi'an Ruimai. The electrochemiluminescence spectrum was obtained by a CCD grating spectrometer of Princeton Instruments Co., Ltd., USA, which was composed of a liquid nitrogen-cooled face array CCD (PyLoN400BRX) detector and an Acton SP2300 monochromator detector with a focal length of 300 mm. The collection of reactive oxygen species was obtained by a Bruker A300 electron spin resonance spectrometer (λ>420 nm) of Germany. The cyclic voltammetry driving was completed by a VersaSTAT 3 of Princeton Co., Ltd., USA, and the collection time of the electrochemiluminescence spectrum driven by cyclic voltammetry was 64 seconds.

[0090] Example 1

[0091] A preparation method of a highly monochromatic gold nanocluster with a radiation band in the blue-green light region, the steps are as follows:

[0092] (1) Take 35.5 μL of 100 mg / mL HAuCl4·3H2O, add 2.5 mL of deionized water;

[0093] (2) Add 50 μL of mercaptopropionic acid to step (1) and stir for 15 min;

[0094] (3) Add 430 μL of 1M sodium hydroxide to step (2) to adjust the pH to 8.5;

[0095] (4) To step (3), 0.5 mL of 0.1 M zinc acetate was added, and the reaction was stirred at room temperature for 6 h. After the reaction was completed, the product was purified by washing with isopropanol, dissolved in deionized water, and Zn 2+ A monodisperse solution of aggregation-induced gold nanoclusters.

[0096] Product characterization:

[0097] The Zn 2+ The UV absorption spectrum of the aggregation-induced gold nanoclusters is shown in Figure 1 From Figure 1 it can be seen that the Zn 2+ The UV absorption characteristic peak of the aggregation-induced gold nanoclusters is at 355 nm and 450 nm.

[0098] The Zn 2+ The photoluminescence spectrum of the aggregation-induced gold nanoclusters is shown in Figure 1 From Figure 1 it can be seen that the Zn 2+ The photoluminescence characteristic peak of the aggregation-induced gold nanoclusters is at 485 nm, and the half-peak width is 25 nm.

[0099] The Zn 2+ The fluorescence lifetime of the aggregation-induced gold nanoclusters is shown in Figure 2 From Figure 2 it can be seen that the Zn 2+ The fluorescence lifetime of the aggregation-induced gold nanoclusters is 31 ns.

[0100] The Zn 2+ The transmission electron microscopy image of the aggregation-induced gold nanoclusters is shown in Figure 3 From Figure 3 it can be seen that the Zn 2+ The aggregation-induced gold nanoclusters are substantially spherical, and the average size is 4.4 nm.

[0101] The Zn 2+ The elemental distribution map of the aggregation-induced gold nanoclusters is shown in Figure 4 From Figure 4 it can be seen that the Zn 2+ The aggregation-induced gold nanocluster nanoclusters are composed of Au, S, Zn, and other elements.

[0102] The Zn 2+ The infrared spectrum of the aggregation-induced gold nanoclusters is shown in Figure 5 From Figure 5 it can be seen that the Zn 2+ The aggregation-induced gold nanocluster nanoclusters have a large number of carboxyl groups on the surface.

[0103] Stability:

[0104] The Zn 2+Aggregation-induced gold nanoclusters were placed at 4°C for 2 months, 4 months, and 6 months, respectively.

[0105] Zn after 2 months 2+ Photoluminescence pattern of aggregation-induced gold nanoclusters as shown in Figure 1 Figure 6 As shown, by Figure 6 It can be seen that Zn 2 + The photoluminescence intensity of the aggregated gold nanoclusters remained almost unchanged after two months of storage.

[0106] Zn after 4 months 2+ Photoluminescence pattern of aggregation-induced gold nanoclusters as shown in Figure 1 Figure 7 As shown, by Figure 7 It can be seen that Zn 2 + The photoluminescence intensity of the aggregated gold nanoclusters remained almost unchanged after 4 months of storage.

[0107] Zn after 6 months 2+ Photoluminescence pattern of aggregation-induced gold nanoclusters as shown in Figure 1 Figure 8 As shown, by Figure 8 It can be seen that Zn 2 + The photoluminescence intensity of the aggregated gold nanoclusters remained almost unchanged after 6 months of storage.

[0108] Example 2

[0109] The method for constructing a highly monochromatic electrochemiluminescence system with high intensity in the blue-green light region comprises the following steps:

[0110] Using a gold electrode as the working electrode, a platinum wire as the counter electrode, an Ag / AgCl electrode as the reference electrode, 10 mM Hepes (pH 7.4) as the buffer solution, and 10 mM hydrazine hydrate as the co-reactant, 0.15 mg / mL Zn prepared in Example 1 was used. 2+ Aggregation-induced gold nanoclusters were used as luminescent reagents to drive cyclic voltammetric scans of monodisperse solutions containing Hepes buffer, co-reactant, and luminescent reagent.

[0111] The electrochemiluminescence intensity-(potential)-time curves obtained using cyclic voltammetry (potential window 0–1.6 V, scan rate 50 mV / s, onset potential 0 V, initial scan direction positive) are shown below. Figure 9 As shown, Figure 9 It can be seen that the electrochemiluminescence system of the present invention can produce redox electrochemiluminescence at 0.74V in 10mM Hepes at pH=7.4.

[0112] The electrochemiluminescence spectrum obtained by cyclic voltammetry (potential window 0–1.6 V, scan rate 50 mV / s, onset potential 0 V, initial scan direction positive) is shown below. Figure 10 As shown, Figure 10 It can be seen that the electrochemiluminescence system of the present invention can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm and a full width at half maximum (FWHM) of 36 nm in 10 mM Hepes at pH 7.4.

[0113] Example 3

[0114] The construction method is the same as that described in Example 2, except that:

[0115] Replace the concentrations of the Hepes buffer solution at pH 7.4 with 5 mM, 15 mM, and 20 mM, respectively.

[0116] A gold electrode was used as the working electrode, a platinum wire as the counter electrode, an Ag / AgCl electrode as the reference electrode, Hepes solutions of different concentrations at pH 7.4 as buffer solutions, 10 mM hydrazine hydrate as a co-reactant, and 0.15 mg / mL Zn. 2+ Aggregation-induced gold nanoclusters were used as luminescent reagents to drive electrochemical cyclic voltammetry in monodisperse solutions containing Hepes buffer, co-reactant, and luminescent reagent.

[0117] Cyclic voltammetry is used for driving the scan, with a potential window of 0–1.6 V, a scan rate of 50 mV / s, a starting potential of 0 V, and a positive initial scan direction.

[0118] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectra of the aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, and 5 mM Hepes luminescence system at pH 7.4 are shown below. Figure 11 As shown in the figure, Zn 2+ Aggregation-induced gold nanoclusters / hydrazine hydrate can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm and a full width at half maximum (FWHM) of 36 nm in 5 mM Hepes at pH 7.4. The electrochemiluminescence intensity is lower than that in 10 mM Hepes buffer solution at pH 7.4.

[0119] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectra of the aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, and 15 mM Hepes luminescence system at pH 7.4 are shown below. Figure 12 As shown in the figure, Zn 2+The aggregation-induced gold nanoclusters / hydrazine hydrate in 15 mM Hepes buffer solution with pH = 7.4 can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm, and a half-peak width of 36 nm, and the electrochemiluminescence intensity is slightly lower than the corresponding intensity in 10 mM Hepes buffer solution with pH = 7.4.

[0120] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, and 20 mM Hepes buffer solution with pH = 7.4 is shown in FIG. 2. Figure 13 As can be seen from the figure, the Zn 2+ The aggregation-induced gold nanoclusters / hydrazine hydrate in 20 mM Hepes buffer solution with pH = 7.4 can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm, and a half-peak width of 36 nm, but the electrochemiluminescence intensity is lower than the corresponding intensity in 10 mM Hepes buffer solution with pH = 7.4.

[0121] As can be seen from Example 3, compared with different light-emitting systems, the corresponding electrochemiluminescence intensity in 10 mM Hepes buffer solution with pH = 7.4 is the strongest.

[0122] Example 4

[0123] The construction method is the same as that described in Example 2, except that:

[0124] The concentration of hydrazine hydrate is replaced by 5 mM, 15 mM, and 20 mM, respectively.

[0125] A gold electrode is used as a working electrode, a platinum wire is used as a counter electrode, an Ag / AgCl electrode is used as a reference electrode, 10 mM Hepes buffer solution with pH = 7.4 is used as a buffer solution, and hydrazine hydrate with different concentrations is used as a co-reactant, and 0.15 mg / mL Zn 2+ The aggregation-induced gold nanoclusters are used as a light-emitting reagent, and a monodisperse solution containing a Hepes buffer solution, a co-reactant, and a light-emitting reagent is driven by electrochemical cyclic voltammetry.

[0126] The driving is carried out by cyclic voltammetry, the potential window is 0-1.6 volts, the scanning speed is 50 millivolts per second, the initial potential is 0 V, and the initial scan is positive.

[0127] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 5 mM hydrazine hydrate, and 15 mM Hepes buffer solution with pH = 7.4 is shown in FIG. 4. Figure 14 As can be seen from the figure, the Zn 2+The aggregation-induced gold nanoclusters in 10 mM pH = 7.4 Hepes containing 5 mM hydrazine hydrate can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm, and a half-peak width of 36 nm, and the electrochemiluminescence intensity is lower than the corresponding intensity when the concentration of hydrazine hydrate is 10 mM.

[0128] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 15 mM hydrazine hydrate, and 15 mM pH = 7.4 Hepes luminescence system is shown in Figure 15 As can be seen from the figure, the Zn 2+ The aggregation-induced gold nanoclusters in 10 mM pH = 7.4 Hepes containing 15 mM hydrazine hydrate can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm, and a half-peak width of 36 nm, and the electrochemiluminescence intensity is lower than the corresponding intensity when the concentration of hydrazine hydrate is 10 mM.

[0129] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 20 mM hydrazine hydrate, and 15 mM pH = 7.4 Hepes luminescence system is shown in Figure 16 As can be seen from the figure, the Zn 2+ The aggregation-induced gold nanoclusters in 10 mM pH = 7.4 Hepes containing 20 mM hydrazine hydrate can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm, and a half-peak width of 36 nm, and the electrochemiluminescence intensity is lower than the corresponding intensity when the concentration of hydrazine hydrate is 10 mM.

[0130] As can be seen from Example 4, compared with different luminescence systems, the electrochemiluminescence intensity corresponding to the concentration of 10 mM hydrazine hydrate is the strongest.

[0131] Example 5

[0132] The construction method is the same as that described in Example 2, except that:

[0133] The concentration of Zn 2+ The concentration of the aggregation-induced gold nanoclusters is replaced with 0.10 mg / mL, 0.20 mg / mL, and 0.25 mg / mL, respectively.

[0134] A gold electrode is used as a working electrode, a platinum wire is used as a counter electrode, an Ag / AgCl electrode is used as a reference electrode, 10 mM pH = 7.4 Hepes is used as a buffer solution, 10 mM hydrazine hydrate is used as a co-reactant, and different Zn 2+ The aggregation-induced gold nanoclusters are used as a luminescent reagent, and a monodisperse solution containing a Hepes buffer solution, a co-reactant, and a luminescent reagent is driven by electrochemical cyclic voltammetry.

[0135] Cyclic voltammetry driving, potential window is 0-1.6 volts, scanning speed is 50 millivolt / second, initial potential is 0V, initial scanning is positive;

[0136] 0.10mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced nanogold cluster, 10mM hydrazine hydrate, 10mM pH=7.4 Hepes light emitting system is as shown in Figure 17 As can be seen from the figure, 0.10mg / mL Zn 2+ The aggregation-induced nanogold cluster can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485nm in 10mM pH=7.4 Hepes containing 10mM hydrazine hydrate, with a half-peak width of 36nm, and the electrochemiluminescence intensity is lower than that of Zn 2+ The corresponding intensity of the aggregation-induced nanogold cluster is 0.15mg / mL.

[0137] 0.20mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced nanogold cluster, 10mM hydrazine hydrate, 10mM pH=7.4 Hepes light emitting system is as shown in Figure 18 As can be seen from the figure, 0.20mg / mL Zn 2+ The aggregation-induced nanogold cluster can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485nm in 10mM pH=7.4 Hepes containing 10mM hydrazine hydrate, with a half-peak width of 36nm, and the electrochemiluminescence intensity is lower than that of Zn 2+ The corresponding intensity of the aggregation-induced nanogold cluster is 0.15mg / mL.

[0138] 0.25mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced nanogold cluster, 10mM hydrazine hydrate, 10mM pH=7.4 Hepes light emitting system is as shown in Figure 19 As can be seen from the figure, 0.25mg / mL Zn 2+ The aggregation-induced nanogold cluster can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485nm in 10mM pH=7.4 Hepes containing 10mM hydrazine hydrate, with a half-peak width of 36nm, and the electrochemiluminescence intensity is lower than that of Zn 2+ The corresponding intensity of the aggregation-induced nanogold cluster is 0.15mg / mL.

[0139] As can be seen from Example 5, by comparing different light emitting systems, the electrochemiluminescence intensity of the aggregation-induced nanogold cluster is the strongest when the concentration of the aggregation-induced nanogold cluster is 0.15mg / mL. 2+ The electrochemiluminescence intensity of the aggregation-induced nanogold cluster is the strongest when the concentration of the aggregation-induced nanogold cluster is 0.15mg / mL.

[0140] Example 6

[0141] The construction method is the same as described in Example 2, except that:

[0142] The Zn 2+ The aggregation-induced gold nanoclusters prepared in Example 1 were placed at 4℃ for 2 months, 4 months and 6 months respectively, and the Zn 2+ The aggregation-induced gold nanoclusters are used as a luminescent reagent.

[0143] A gold electrode was used as a working electrode, a platinum wire as a counter electrode, an Ag / AgCl electrode as a reference electrode, 10 mM pH=7.4 Hepes as a buffer solution, 10 mM hydrazine hydrate as a co-reagent, and the Zn 2+ The aggregation-induced gold nanoclusters are used as a luminescent reagent, and the Zn 2+ The concentration of the aggregation-induced gold nanoclusters was 0.15 mg / mL, and a monodispersed solution containing a Hepes buffer solution, a co-reagent and a luminescent reagent was driven by electrochemical cyclic voltammetry.

[0144] The driving method was cyclic voltammetry, the potential window was 0-1.6 volts, the scanning speed was 50 millivolts per second, the initial potential was 0 V, and the initial scan was positive.

[0145] The Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters / hydrazine hydrate / Hepes luminescent system is shown in Figure 20 As can be seen from the figure, the Zn 2+ The aggregation-induced gold nanoclusters can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm in 10 mM pH=7.4 Hepes containing 10 mM hydrazine hydrate, with a half-peak width of 36 nm, and the electrochemiluminescence intensity is basically consistent with that of Example 2.

[0146] The Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters / hydrazine hydrate / Hepes luminescent system is shown in Figure 21 As can be seen from the figure, the Zn 2+ The aggregation-induced gold nanoclusters can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm in 10 mM pH=7.4 Hepes containing 10 mM hydrazine hydrate, with a half-peak width of 36 nm, and the electrochemiluminescence intensity is basically consistent with that of Example 2.

[0147] The Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters / hydrazine hydrate / Hepes luminescent system is shown inFigure 22 As shown in the figure, Zn 2+ The aggregation-induced nanogold cluster can produce a highly monochromatic electrochemiluminescence signal with a maximum emission wavelength of 485 nm in 10 mM pH=7.4 Hepes containing 10 mM hydrazine hydrate, and the half-peak width is 36 nm, and the electrochemiluminescence intensity is basically consistent with that of Example 2.

[0148] As can be seen from Example 6, Zn 2+ The electrochemiluminescence intensity of the aggregation-induced nanogold cluster is basically maintained stable, and the highly monochromatic electrochemiluminescence system constructed in the blue-green light region is stable in water phase.

[0149] Comparative Example 1

[0150] The construction method is the same as that described in Example 3, except that:

[0151] The luminescent reagent Zn 2+ The aggregation-induced nanogold cluster is removed.

[0152] The gold electrode is used as the working electrode, the platinum wire is used as the counter electrode, the Ag / AgCl electrode is used as the reference electrode, 10 mM pH=7.4 Hepes is used as the buffer solution, and 10 mM hydrazine hydrate is used as the co-reactant. The electrochemiluminescence spectrum obtained by cyclic voltammetry driving (the potential window is 0-1.6 volts, the scanning speed is 50 millivolts / second, the initial potential is 0 V, and the initial scan is positive) is as shown in Figure 23 As shown in the figure, no electrochemiluminescence signal can be produced in 10 mM pH=7.4 Hepes containing 10 mM hydrazine hydrate.

[0153] Comparative Example 2

[0154] The construction method is the same as that described in Example 3, except that:

[0155] The Hepes buffer solution is replaced by carbonate with pH=9.4, acetate with pH=7.4, citrate with pH=7.4, phosphate with pH=7.4, and Tris-HCl with pH=7.4, respectively.

[0156] The gold electrode is used as the working electrode, the platinum wire is used as the counter electrode, the Ag / AgCl electrode is used as the reference electrode, 10 mM different buffer solutions, and 10 mM hydrazine hydrate is used as the co-reactant, and 0.15 mg / mL Zn 2+ The aggregation-induced nanogold cluster is used as the luminescent reagent, and the monodisperse solution containing different buffer solutions, co-reactants and luminescent reagents is driven by electrochemical cyclic voltammetry.

[0157] Cyclic voltammetry driving, potential window is 0-1.6 volts, scanning speed is 50 millivolt / second, initial potential is 0V, initial scanning is positive;

[0158] 0.15mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 10 mM carbonate with pH=9.4 as the buffer solution light system is shown in Figure 24 As can be seen from the figure, Zn 2+ The aggregation-induced gold nanoclusters can only produce weak electrochemiluminescence signal in 10 mM carbonate with pH=9.4 containing 10 mM hydrazine hydrate.

[0159] 0.15mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 10 mM citrate with pH=7.4 as the buffer solution light system is shown in Figure 25 As can be seen from the figure, Zn 2+ The aggregation-induced gold nanoclusters cannot produce electrochemiluminescence signal in 10 mM citrate with pH=7.4 containing 10 mM hydrazine hydrate.

[0160] 0.15mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 10 mM phosphate with pH=7.4 as the buffer solution light system is shown in Figure 26 As can be seen from the figure, Zn 2+ The aggregation-induced gold nanoclusters cannot produce electrochemiluminescence signal in 10 mM phosphate with pH=7.4 containing 10 mM hydrazine hydrate.

[0161] 0.15mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM hydrazine hydrate, 10 mM Tris-HCl with pH=7.4 as the buffer solution light system is shown in Figure 27 As can be seen from the figure, Zn 2+ The aggregation-induced gold nanoclusters cannot produce electrochemiluminescence signal in 10 mM Tris-HCl with pH=7.4 containing 10 mM hydrazine hydrate.

[0162] Comparative Example 3

[0163] The construction method is the same as that described in Example 3, except that:

[0164] The co-reagent is replaced by tripropylamine, triethylamine, triethanolamine, and hydrogen peroxide, respectively.

[0165] The gold electrode is used as the working electrode, the platinum wire is used as the counter electrode, the Ag / AgCl electrode is used as the reference electrode, 10 mM pH=7.4 Hepes, 10 mM tripropylamine, triethylamine, triethanolamine or hydrogen peroxide is used as the co-reaction agent, and 0.15 mg / mL Zn 2+ The aggregation-induced gold nanoclusters are used as the luminescent reagent, and the monodispersed solution containing different buffer solutions, co-reaction agents and luminescent reagents is driven by electrochemical cyclic voltammetry.

[0166] The driving is carried out by cyclic voltammetry, the potential window is 0-1.6 volts, the scanning speed is 50 mV / s, the initial potential is 0 V, and the initial scanning is positive.

[0167] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM tripropylamine and 10 mM pH=7.4 Hepes luminescent system is shown in Figure 28 As shown in the figure, the Zn 2+ The aggregation-induced gold nanoclusters cannot produce electrochemiluminescence signals in 10 mM pH=7.4 Hepes containing 10 mM tripropylamine.

[0168] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM triethylamine and 10 mM pH=7.4 Hepes luminescent system is shown in Figure 29 As shown in the figure, the Zn 2+ The aggregation-induced gold nanoclusters can only produce weak electrochemiluminescence signals in 10 mM pH=7.4 Hepes containing 10 mM triethylamine.

[0169] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM triethanolamine and 10 mM pH=7.4 Hepes luminescent system is shown in Figure 30 As shown in the figure, the Zn 2+ The aggregation-induced gold nanoclusters cannot produce electrochemiluminescence signals in 10 mM pH=7.4 Hepes containing 10 mM triethanolamine.

[0170] 0.15 mg / mL Zn 2+ The electrochemiluminescence spectrum of the aggregation-induced gold nanoclusters, 10 mM hydrogen peroxide and 10 mM pH=7.4 Hepes luminescent system is shown in Figure 31 As shown in the figure, the Zn 2+ The aggregation-induced gold nanoclusters cannot produce electrochemiluminescence signals in 10 mM pH=7.4 Hepes containing 10 mM hydrogen peroxide.

[0171] In summary: only in Hepes buffer containing a specific co-reactant (hydrazine hydrate), Zn 2+ Only the aggregation-induced gold nanoclusters can produce highly monochromatic electrochemiluminescence; tripropylamine, triethylamine, triethanolamine, hydrogen peroxide cannot produce highly monochromatic electrochemiluminescence in the blue-green light region. Carbonate, acetate, citrate, phosphate, Tris-HCl also cannot produce highly monochromatic electrochemiluminescence in the blue-green light region.

Claims

1. A method for constructing a highly monochromatic electrochemiluminescence system with high intensity in the blue-green light region, comprising the following steps: A gold electrode was used as the working electrode, a platinum wire as the counter electrode, an Ag / AgCl electrode as the reference electrode, 10 mM Hepes (pH 7.4) as the buffer solution, 10 mM hydrazine hydrate as the co-reactant, and 0.15 mg / mL Zn. 2+ Aggregation-induced gold nanoclusters, used as luminescent agents, were used to drive a monodisperse solution containing Hepes buffer, co-reactant, and luminescent agent through cyclic voltammetry scanning. They were able to produce electrochemiluminescence radiation with a full width at half maximum (FWHM) of 36 nm at 485 nm. The characteristic emission wavelength of the Zn²⁺ aggregation-induced gold nanoclusters was at 485 nm with a FWHM of 25 nm, and the characteristic ultraviolet absorption peaks were at 355 nm and 450 nm, with a fluorescence lifetime of 31 ns. Zn 2+ The preparation method of aggregation-induced gold nanoclusters includes the following steps: (1) Take 35.5 μL of 100 mg / mL HAuCl4·3H2O and add 2.5 mL of deionized water; (2) Add 50 μL of mercaptopropionic acid to step (1) and stir for 15 min; (3) Add 430 μL of 1M sodium hydroxide to step (2) and adjust the pH to 8.5; (4) Add 0.5 mL of 0.1 M zinc acetate to step (3), stir the mixture at room temperature for 6 h. After the reaction is complete, wash the product with isopropanol and then dissolve it in deionized water to obtain Zn. 2+ Monodisperse solution of aggregation-induced gold nanoclusters.

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