An electrochemiluminescence system based on aerogel enhancement and construction method

Abstract

The present invention relates to an aerogel-enhanced electrochemiluminescence system and a construction method. The present invention prepares CdSe quantum dots into an aerogel structure and uses CdSe Aerogel as a luminescent reagent. The CdSe Aerogel aerogel ensures direct connection and strong electrical coupling between adjacent quantum dots. Due to the particularity of the aerogel structure, quantum dots far from the electrode surface can still be effectively oxidized, thereby generating effectively enhanced electrochemiluminescence. This system can not only generate several-fold enhanced annihilation-type electrochemiluminescence, but also generate 23-116 times the coreactant-type cathode electrochemiluminescence and 126 times the coreactant-type anodic electrochemiluminescence. This broadens the types of high-intensity electrochemiluminescence systems and has strong versatility.

Description

Technical Field

[0001] The invention relates to an electrochemiluminescence system based on aerogel enhancement and a construction method, belonging to the technical field of electrochemiluminescence. Background Art

[0002] Electrochemiluminescence (ECL) is the luminescence phenomenon produced by the return of an ECL active substance to its ground state after an electron transfer process near an electrode surface (Science 1964, 145, 808-809). Due to its advantages of requiring no excitation light source, high sensitivity, and good controllability, it has been widely promoted and applied in many fields, including chemistry, biology, basic medicine, and clinical diagnosis.

[0003] Quantum dots (QDs) are nanoscale semiconductors that have tunable optical, electronic, and surface chemical properties. Since 2002, they have shown great application prospects in the field of electrochemiluminescence as a new generation of ideal luminescent materials (Science 2002, 296, 1293-1297). Although the ECL performance of various QDs (such as Si, Ge, CdSe, CdSe / CdS, CdSe / ZnSe, CdTe, CdS, and PbS) has been systematically studied over the past 20 years, the ECL efficiency of QDs is still significantly insufficient compared to photoluminescence.

[0004] To address this issue, a variety of methods have been developed to enhance the electrochemiluminescence of quantum dots, including element doping, aggregation induction, crystallization induction, introduction of dissolved oxygen, layer-by-layer modification of nanocomposites, and preparation of nanotubes. Element doping introduces new energy levels to the original quantum dots, but complicates the study of the luminescence mechanism. Most reports on various types of induced enhanced electrochemiluminescence are based on hydrocarbon nanocrystals and molecular compounds. The introduction of dissolved oxygen involves a variety of reactive oxygen species, and the mechanism by which it enhances electrochemiluminescence remains unclear. Compared to monodispersed and single-layer surface-modified electrodes, layer-by-layer modification of nanocomposites requires multiple, complex electrode surface treatments, making the testing process more complex. Due to the large surface area and hydrophobicity of nanotubes, the adsorption of impurities by them can alter the test buffer and their own environment.

[0005] Therefore, there is an urgent need to explore a new, simple and effective method to enhance the electrochemiluminescence of quantum dots and expand the types of high-intensity electrochemiluminescence systems. Summary of the Invention

[0006] In view of the defects of existing enhanced electrochemiluminescence methods, the present invention provides an aerogel-enhanced electrochemiluminescence system and a construction method.

[0007] S in the present invention 2- Stable CdSe / ZnCdS quantum dot aerogel, referred to as CdSe Aerogel. Summary of the invention:

[0009] The present invention uses CdSe Aerogel as a luminescent reagent. CdSe Aerogel ensures direct connection and strong electrical coupling between adjacent quantum dots. Due to the special structure of the aerogel, quantum dots far away from the electrode surface can still be effectively oxidized, thereby producing effectively enhanced electrochemiluminescence. This not only avoids the shortcomings of existing methods, but also broadens the types of high-intensity electrochemiluminescence systems and has strong versatility.

[0010] Terminology Notes:

[0011] Room temperature: The room temperature mentioned in the present invention has a conventional meaning, and the temperature range is 25±5℃. Detailed description of the invention:

[0013] To achieve the above object, the present invention is implemented through the following technical solutions:

[0014] An electrochemiluminescence system based on aerogel enhancement, using S 2- The stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent reagent to form a co-reactant type or annihilation type electrochemiluminescence system in the presence of a buffer solution.

[0015] According to the preferred embodiment of the present invention, in the electrochemiluminescence system, S 2- The concentration of stable CdSe / ZnCdS quantum dot aerogel is 0.1-1 mg / mL.

[0016] Most preferably, in the electrochemiluminescence system, S 2- The concentration of the stable CdSe / ZnCdS quantum dot aerogel is 0.5 mg / mL.

[0017] According to the preferred embodiment of the present invention, S 2- Stable CdSe / ZnCdS quantum dot aerogels were prepared as follows:

[0018] Firstly, CdO was used as cadmium source, Se powder as selenium source, octadecene and oleic acid as stabilizers to prepare CdSe / CdZnS core-shell quantum dots stabilized by long-chain organic ligands. Then (NH4)2S was used for ligand exchange. After micro-hydrogelation and supercritical drying, S 2- Stable CdSe / ZnCdS quantum dot aerogel; wherein the molar ratio of CdO:myristic acid is 1:3; and the molar ratio of CdO:Se is 2:1.

[0019] A preferred embodiment of the present invention:

[0020] S 2- The specific preparation method of stable CdSe / ZnCdS quantum dot aerogel is as follows:

[0021] (1) 4 mmol CdO (513 mg), 12 mmol myristic acid (2.74 g) and 20 mL 1-octadecene (ODE) were mixed evenly and degassed at room temperature for 15 min. After the reaction apparatus was filled with argon, the mixture was heated to 270 °C until the CdO was completely dissolved; the mixture was cooled to 90 °C and degassed at this temperature for 1 h. After filling with argon, 20 mL dry ODE was added and degassed at 80 °C for 1 h. After degassed, the temperature was raised to 240 °C and the Se ODE suspension was quickly added. The temperature was maintained at 240 °C for 5 min to achieve the growth of CdSe quantum dot cores. After the growth was completed, the temperature was lowered to 180 °C and 1 mL 2-ethylhexanoic acid and 4 mL oleic acid (OlAc) were added to the reaction system;

[0022] (2) 7 mmol of thiourea was dissolved in 6 mL of triethylene glycol dimethyl ether, and 2.88 mL of zinc 2-ethylhexanoate was added. The resulting mixed solution was divided into three equal parts; the mixture was slowly injected into the system obtained in step (1) at 180°C for three times to grow the shell for 10 min. The mixture was cooled to room temperature and centrifuged with isopropanol and acetonitrile respectively to obtain CdSe / ZnCdS-S 2- core / shell quantum dots;

[0023] (3) CdSe / ZnCdS-S 2- The hexane solution of core / shell quantum dots was mixed with the NMF solution of (NH4)2S and stirred vigorously. The quantum dots were completely transferred from the upper hexane phase to the lower NMF phase, and the ligand exchange was successful. The NMF phase was washed with hexane 5-8 times, the NMF phase was collected, and two volumes of acetone were added and centrifuged to precipitate the quantum dots. The resulting precipitate was redispersed in NMF and filtered through a membrane. The precipitate was vacuum dried at room temperature overnight to obtain S 2- Stable CdSe / ZnCdS quantum dots;

[0024] (4) S 2- Stable CdSe / ZnCdS quantum dots are added to a NMF solution to form a mixed solution. Water at a volume ratio of 1.5-2.5% (v / v) of the quantum dots is added to the mixed solution and maintained for 2-7 days for gelation to obtain a hydrogel. The obtained hydrogel is washed with ethanol 20-30 times to remove residues. The ethanol is replaced with liquid carbon dioxide and supercritical drying is performed to obtain an aerogel.

[0025] According to the preferred embodiment of the present invention, CdSe / ZnCdS-S 2-The volume ratio of core / shell quantum dots to hexane is (1-2): (1-2), and the most preferred is CdSe / ZnCdS-S 2- The volume ratio of core / shell quantum dots to hexane was 1:1.

[0026] According to the present invention, preferably, the concentration of (NH4)2S in the NMF solution of (NH4)2S is 3-7mM; most preferably, the concentration of (NH4)2S in the NMF solution of (NH4)2S is 5mM.

[0027] According to the preferred embodiment of the present invention, CdSe / ZnCdS-S 2- The volume ratio of the hexane solution of core / shell quantum dots and the NMF solution of (NH4)2S was 1:5.

[0028] According to the preferred embodiment of the present invention, S 2- The characteristic emission wavelength of the stable CdSe / ZnCdS quantum dot aerogel is 610nm, the characteristic UV absorption peaks are at 525nm and 580nm, and the fluorescence lifetime is 11.75ns.

[0029] According to the present invention, preferably, for the co-reactant type electrochemiluminescent system,

[0030] At the anode, S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent agent, triethanolamine is used as an anode co-reactant, and borate is used as a buffer solution to form an anode co-reactant type electrochemiluminescence system.

[0031] At the cathode, S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent reagent, ammonium persulfate is used as a cathode co-reactant, and one of borate, acetate, carbonate, phosphate or Tris-HCl is used as a buffer solution to form a cathode co-reactant type electrochemiluminescence system.

[0032] According to the present invention, preferably, in the co-reactant type electrochemiluminescence system, the pH of the borate buffer, phosphate buffer, and Tris-HCl buffer is 7.0-7.4, further preferably, the pH of the borate, phosphate, and Tris-HCl buffer is 7.2-7.4, and most preferably, the pH of the borate, phosphate, and Tris-HCl buffer is 7.4;

[0033] The pH of the carbonate buffer solution is 8.8-9.4, more preferably, the pH of the carbonate buffer solution is 8.0-9.2, and most preferably, the pH of the carbonate buffer solution is 9.0;

[0034] The pH of the acetate buffer solution is 6.0-6.6, more preferably, the pH of the acetate buffer solution is 6.3-6.5, and most preferably, the pH of the acetate buffer solution is 6.4.

[0035] Preferably, according to the present invention, in the coreactant-type electrochemiluminescence system, the concentration of the buffer solution is 0.05-0.5M, and most preferably, the concentration of the buffer solution is 0.1M.

[0036] The concentration of the coreactant is 8-12 mM, and most preferably, the concentration of the coreactant is 10 mM.

[0037] According to the present invention, preferably, for the annihilation type electrochemiluminescence system,

[0038] S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent reagent, and borate is used as a buffer solution to form an annihilation-type electrochemiluminescence system.

[0039] Preferably, according to the present invention, in the annihilation-type electrochemiluminescence system, the concentration of the borate buffer solution is 0.05-0.5M, and most preferably, the concentration of the buffer solution is 0.1M.

[0040] The method for constructing the above electrochemiluminescence system comprises the following steps:

[0041] For the co-reactant type electrochemiluminescence system, S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent reagent, triethanolamine or ammonium persulfate is used as a co-reactant, and in the presence of a buffer, a co-reactant-type electrochemiluminescence system is formed. The electrochemiluminescence radiation of this system is driven by a three-electrode system and cyclic voltammetry scanning method.

[0042] For annihilation-type electrochemiluminescence system, S 2- Stable CdSe / ZnCdS quantum dot aerogel CdSe Aerogel is used as a luminescent reagent, and in the presence of a buffer solution, a co-reactant type electrochemiluminescence system is formed; a three-electrode system and a cyclic voltammetry scanning method are used to apply a voltage with an initial positive or negative sweep to drive the system to emit electrochemiluminescence.

[0043] According to the preferred embodiment of the present invention, the electrochemical conditions adopted are: using a gold electrode drop-coated with a luminescent reagent as the working electrode, a platinum wire as the counter electrode, and an Ag / AgCl electrode as the reference electrode, and performing cyclic voltammetry scanning in a buffer solution containing / not containing a co-reactant.

[0044] According to the present invention, preferably, when performing cyclic voltammetry scanning, the scanning voltage range is -1.6 to 1.6 V, the number of scanning circles is 1 to 3 circles, and the scanning speed is 100 to 200 mV / s.

[0045] For co-reactant type electrochemiluminescence system electrochemiluminescence:

[0046] At the anode, CdSe Aerogel was used as the luminescent reagent, triethanolamine as the anode co-reactant, and borate as the buffer solution. A three-electrode system and cyclic voltammetry scanning method were used to drive the system. Compared with the case where CdSe quantum dots were used as the luminescent reagent under the same conditions, the anode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced by 126 times.

[0047] At the cathode, CdSe Aerogel was used as the luminescent reagent, ammonium persulfate as the cathode co-reactant, borate, acetate, carbonate, phosphate or Tris-HCl as the buffer solution, and a three-electrode system and cyclic voltammetry scanning method were used to drive it. Compared with using CdSe quantum dots as the luminescent reagent under the same conditions, the cathode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced by 23 to 116 times.

[0048] For annihilation-type electrochemiluminescence system electrochemiluminescence:

[0049] Using CdSe Aerogel as the luminescent reagent and borate as the buffer solution, a three-electrode system and cyclic voltammetry scanning method were adopted to drive the device. The applied voltage was initially swept in a positive or negative direction. Compared with the case where CdSe quantum dots were used as the luminescent reagent under the same conditions, both the cathode and the anode could achieve a relative enhancement in the electrochemiluminescence signal intensity.

[0050] It is further preferred for the co-reactant type electrochemiluminescent system;

[0051] At the anode, using CdSe Aerogel as the luminescent reagent, triethanolamine as the anode co-reactant, and borate as the buffer solution, the anode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced 126 times compared to using CdSe quantum dots as the luminescent reagent under the same conditions.

[0052] At the cathode, using CdSe Aerogel as the luminescent reagent, ammonium persulfate as the cathode co-reactant, and borate as the buffer solution, the cathode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced 56 times compared to using CdSe quantum dots as the luminescent reagent under the same conditions.

[0053] At the cathode, using CdSe Aerogel as the luminescent reagent, ammonium persulfate as the cathode co-reactant, and acetate as the buffer solution, the cathode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced by 95 times compared to using CdSe quantum dots as the luminescent reagent under the same conditions.

[0054] At the cathode, using CdSe Aerogel as the luminescent reagent, ammonium persulfate as the cathode co-reactant, and carbonate as the buffer solution, the cathode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced 116 times compared to using CdSe quantum dots as the luminescent reagent under the same conditions.

[0055] At the cathode, using CdSe Aerogel as the luminescent reagent, ammonium persulfate as the cathode co-reactant, and phosphate as the buffer solution, the cathode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced by 23 times compared to using CdSe quantum dots as the luminescent reagent under the same conditions.

[0056] At the cathode, using CdSe Aerogel as the luminescent reagent, ammonium persulfate as the cathode co-reactant, and Tris-HCl as the buffer solution, the cathode electrochemiluminescence signal intensity of CdSe Aerogel can be effectively enhanced by 60 times compared to using CdSe quantum dots as the luminescent reagent under the same conditions.

[0057] Further preferred for the annihilation type electrochemiluminescence system;

[0058] Using CdSe Aerogel as the luminescent reagent and borate as the buffer solution, the applied voltage was initially swept towards the positive direction. Compared with using CdSe quantum dots as the luminescent reagent under the same conditions, the annihilation-type electrochemiluminescence signal intensity of CdSe Aerogel was enhanced by 1.5 times and 13 times at the cathode and anode, respectively.

[0059] Using CdSe Aerogel as the luminescent reagent and borate as the buffer solution, the applied voltage was initially swept toward negative. Compared with using CdSe quantum dots as the luminescent reagent under the same conditions, the annihilation-type electrochemiluminescence signal intensity of CdSe Aerogel was enhanced by 1.5 times and 15 times at the cathode and anode, respectively.

[0060] The electrochemiluminescence system of the present invention uses CdSe Aerogel as a luminescent agent. Compared to CdSe QDs, this luminescent agent produces anodic co-reactant-type electrochemiluminescence radiation with a 126-fold increase in electrochemiluminescence signal intensity when driven by potential scanning in a borate buffer containing triethanolamine. It also produces cathodic co-reactant-type electrochemiluminescence radiation with a 23-116-fold increase in electrochemiluminescence signal intensity when driven by potential scanning in a borate, acetate, carbonate, phosphate, or Tris-HCl buffer containing ammonium persulfate. It can also produce annihilation-type electrochemiluminescence radiation with several-fold increase in electrochemiluminescence when driven by potential scanning in a borate buffer. Numerous experiments have confirmed that the luminescent system of the present invention, in the form of an aerogel, can significantly enhance the co-reactant-type and annihilation-type electrochemiluminescence of quantum dots compared to CdSe QDs.

[0061] Beneficial effects of the present invention:

[0062] 1. The present invention uses CdSe Aerogel as a luminescent agent. CdSe Aerogel ensures direct connection and strong electrical coupling between adjacent quantum dots. Due to the special structure of the aerogel, quantum dots far away from the electrode surface can still be effectively oxidized, thereby producing effectively enhanced electrochemiluminescence. This not only avoids the shortcomings of existing methods, but also broadens the types of high-intensity electrochemiluminescence systems and has strong versatility.

[0063] 2. From the perspective of improving and enhancing the electronic coupling between quantum dots, the present invention provides an effective and universal luminescence system and construction method for enhancing the electrochemical luminescence of quantum dots, avoiding the problems of introducing new energy levels caused by conventional means of enhancing electrochemical luminescence.

[0064] 3. The electrochemiluminescence system of the present invention uses CdSe Aerogel as a luminescent agent. In the presence of a buffer solution, it can not only enhance the annihilation-type electrochemiluminescence of quantum dots, but also effectively enhance the electrochemiluminescence of the cathode and anode of the quantum dot co-reactant, broadening the types of high-intensity electrochemiluminescence systems and having strong versatility; it is conducive to the study of the electrochemiluminescence mechanism of quantum dot aerogels. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 is S of Example 1 2- High-magnification transmission electron microscopy image of stable CdSe / ZnCdS quantum dots.

[0066] Figure 2 is S of Example 1 2- XPS elemental spectrum of stable CdSe / ZnCdS quantum dots; the horizontal axis is binding energy and the vertical axis is intensity.

[0067] Figure 3 is S of Example 1 2- XRD diffraction pattern of stable CdSe / ZnCdS quantum dots; the abscissa is the diffraction angle and the ordinate is the diffraction intensity.

[0068] Figure 4 is S of Example 1 2- UV absorption and fluorescence emission spectra of stable CdSe / ZnCdS quantum dots; the horizontal axis is wavelength, and the vertical axis is absorbance / fluorescence intensity.

[0069] Figure 5 is S of Example 1 2- Fluorescence lifetime decay curve of stable CdSe / ZnCdS quantum dots; the horizontal axis is time and the vertical axis is fluorescence intensity.

[0070] Figure 6 This is a high-magnification transmission electron microscope image of CdSe Aerogel in Example 2.

[0071] Figure 7 The UV absorption and fluorescence emission spectra of CdSe Aerogel in Example 2 are shown; the abscissa is wavelength, and the ordinate is absorbance / fluorescence intensity.

[0072] Figure 8 This is the fluorescence lifetime decay curve of CdSe Aerogel in Example 2; the abscissa is time, and the ordinate is fluorescence intensity.

[0073] Figure 9 This is the anodic differential pulse voltammetry curve of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in 0.1 M borate at pH 7.4 in Example 3; the potential window is 0-1.6 V, the scan rate is 100 mV / s; the abscissa is the potential, and the ordinate is the current.

[0074] Figure 10 This is a graph of the electrochemiluminescence intensity-potential (time) curve driven by cyclic voltammetry of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in Example 4 in 0.1 M pH = 7.4 borate containing 10 mM triethanolamine; the potential window is 0-1.6 V, the scan rate is 100 mV / s; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0075] Figure 11 This is the anodic electrochemiluminescence spectrum of the gold electrode in Example 4 drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in 0.1 M pH = 7.4 borate containing 10 mM triethanolamine driven by cyclic voltammetry; the potential window is 0-1.6 V, the scan rate is 100 mV / s; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0076] Figure 12 Anodic spooling electrochemiluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in Example 4, driven by cyclic voltammetry, in 0.1 M borate solution with a pH of 7.4 and 10 mM triethanolamine; potential window 0-1.6 V, scan rate 100 mV / s; wavelength on the x-axis, electrochemiluminescence intensity on the y-axis, and potential on the z-axis.

[0077] Figure 13This is the cathodoluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in Example 5, driven by cyclic voltammetry in 0.1 M borate solution with a pH of 7.4 and 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is wavelength, and the ordinate is electrochemiluminescence intensity.

[0078] Figure 14 This is the cathodoluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in Example 6, driven by cyclic voltammetry in 0.1 M acetate with a pH of 6.4 and 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is wavelength, and the ordinate is electrochemiluminescence intensity.

[0079] Figure 15 This is the cathodoluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in Example 7, driven by cyclic voltammetry in 0.1 M carbonate solution with a pH of 9.0 and 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0080] Figure 16 This is the cathodoluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in Example 8, driven by cyclic voltammetry in 0.1 M phosphate with a pH of 7.4 and 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0081] Figure 17 This is the cathodoluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in Example 9, driven by cyclic voltammetry in 0.1 M Tris-HCl (pH = 7.4) containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is wavelength, and the ordinate is electrochemiluminescence intensity.

[0082] Figure 18 This is the electrochemiluminescence intensity-potential curve driven by cyclic voltammetry of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in 0.1 M borate, pH 7.4, in Example 10; the potential window is -1.4 to 1.4 V, the scan rate is 200 mV / s, the starting potential is 0 V, and the initial scan is positive; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0083] Figure 19 This is the electrochemiluminescence intensity-potential curve driven by cyclic voltammetry of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe Aerogel in 0.1 M borate, pH = 7.4, in Example 10; the potential window is -1.4 to 1.4 V, the scan rate is 200 mV / s, the starting potential is 0 V, and the initial scan is negative; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0084] Figure 20 This is the anodic differential pulse voltammetry curve of the bare gold electrode in 0.1M pH = 7.4 borate in Comparative Example 1; the potential window is 0-1.6V, the scan rate is 100 mV / s; the abscissa is the potential, and the ordinate is the current.

[0085] Figure 21 This is the anodic differential pulse voltammetry curve of the gold electrode in Comparative Example 2, which was drop-coated with 5 μL of 0.5 mg / mL CdSe QDs, in 0.1 M pH = 7.4 borate; the potential window is 0-1.6 V, the scan rate is 100 mV / s; the abscissa is the potential, and the ordinate is the current.

[0086] Figure 22 This is the electrochemiluminescence intensity-potential (time) curve of the cyclic voltammetry-driven electrochemiluminescence of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in Comparative Example 3 in 0.1 M pH = 7.4 borate containing 10 mM triethanolamine; the potential window is 0-1.6 V, the scan rate is 100 mV / s; the horizontal axis is the potential, and the vertical axis is the electrochemiluminescence intensity.

[0087] Figure 23 Anodic electrochemiluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in Comparative Example 3 driven by cyclic voltammetry in 0.1 M pH = 7.4 borate containing 10 mM triethanolamine; potential window 0-1.6 V, scan rate 100 mV / s; potential on the abscissa, electrochemiluminescence intensity on the ordinate.

[0088] Figure 24 Anodic spooling electrochemiluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in Comparative Example 3, driven by cyclic voltammetry, in 0.1 M pH = 7.4 borate containing 10 mM triethanolamine; potential window 0-1.6 V, scan rate 100 mV / s; X-axis is wavelength, Y-axis is electrochemiluminescence intensity, and Z-axis is potential.

[0089] Figure 25This is the cathode electrochemiluminescence spectrum of the gold electrode in Comparative Example 4 drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in 0.1 M pH = 7.4 borate containing 10 mM ammonium persulfate driven by cyclic voltammetry; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the horizontal axis is wavelength, and the vertical axis is electrochemiluminescence intensity.

[0090] Figure 26 This is a graph of the electrochemiluminescence intensity-potential (time) curve of the cyclic voltammetry-driven electrochemiluminescence intensity of the bare gold electrode in Comparative Example 5 in 0.1 M pH = 7.4 borate containing 10 mM triethanolamine; the potential window is 0-1.6 V, the scan rate is 100 mV / s; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0091] Figure 27 This is the cathode electrochemiluminescence spectrum of the bare gold electrode in Comparative Example 6 driven by cyclic voltammetry in 0.1 M pH = 7.4 borate containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0092] Figure 28 This is the cathode electrochemiluminescence spectrum of the bare gold electrode in Comparative Example 7 driven by cyclic voltammetry in 0.1 M pH = 6.4 acetate containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0093] Figure 29 This is the cathodoluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in Example 8, driven by cyclic voltammetry in 0.1 M pH = 6.4 acetate containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0094] Figure 30 This is the cathode electrochemiluminescence spectrum of the bare gold electrode in Comparative Example 9 driven by cyclic voltammetry in 0.1 M pH = 9.0 carbonate containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0095] Figure 31This is the cathodic electrochemiluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in Example 10, driven by cyclic voltammetry in 0.1 M pH = 9.0 carbonate containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0096] Figure 32 This is the cathode electrochemiluminescence spectrum of the bare gold electrode in Comparative Example 11 driven by cyclic voltammetry in 0.1 M pH = 7.4 phosphate containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0097] Figure 33 This is the cathode electrochemiluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in Example 12, driven by cyclic voltammetry in 0.1 M pH = 7.4 phosphate containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the horizontal axis is the wavelength, and the vertical axis is the electrochemiluminescence intensity.

[0098] Figure 34 This is the cathode electrochemiluminescence spectrum of the bare gold electrode in Comparative Example 13 driven by cyclic voltammetry in 0.1 M pH = 7.4 Tris-HCl containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the abscissa is the wavelength, and the ordinate is the electrochemiluminescence intensity.

[0099] Figure 35 This is the cathode electrochemiluminescence spectrum of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in Example 14, driven by cyclic voltammetry in 0.1 M pH = 7.4 Tris-HCl containing 10 mM ammonium persulfate; the potential window is 0 to -1.6 V, the scan rate is 100 mV / s; the horizontal axis is the wavelength, and the vertical axis is the electrochemiluminescence intensity.

[0100] Figure 36 This is the electrochemiluminescence intensity-potential curve driven by cyclic voltammetry of the bare gold electrode in 0.1 M pH = 7.4 borate in Comparative Example 15; the potential window is -1.4 to 1.4 V, the scan rate is 200 mV / s, the starting potential is 0 V, and the initial scan is positive; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0101] Figure 37This is the electrochemiluminescence intensity-potential curve driven by cyclic voltammetry of the bare gold electrode in 0.1 M pH = 7.4 borate in Comparative Example 15; the potential window is -1.4 to 1.4 V, the scan rate is 200 mV / s, the starting potential is 0 V, and the initial scan is negative; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0102] Figure 38 This is the electrochemiluminescence intensity-potential curve of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in 0.1 M pH = 7.4 borate driven by cyclic voltammetry in Example 16; the potential window is -1.4 to 1.4 V, the scan rate is 200 mV / s, the starting potential is 0 V, and the initial scan is positive; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity.

[0103] Figure 39 This is the electrochemiluminescence intensity-potential curve of the gold electrode drop-coated with 5 μL of 0.5 mg / mL CdSe QDs in 0.1 M pH = 7.4 borate driven by cyclic voltammetry in Example 16; the potential window is -1.4 to 1.4 V, the scan rate is 200 mV / s, the starting potential is 0 V, and the initial scan is negative; the abscissa is the potential, and the ordinate is the electrochemiluminescence intensity. DETAILED DESCRIPTION

[0104] The present invention is further illustrated by the following examples, but is not limited thereto.

[0105] In the examples, the preparation of CdSe Aerogeld was carried out using a dryer equipped with a critical point dryer 13200J0AB (SpiSupplies) and a CO2 pump, which is a prior art.

[0106] The electrochemiluminescence-potential curve was collected by Xi'an Ruimai's MPI-II electrochemiluminescence analyzer.

[0107] The electrochemiluminescence spectrum was acquired by a CCD grating spectrometer from Princeton Instrument Co., Ltd., USA, which consisted of a liquid nitrogen-cooled area array CCD (PyLoN400BRX) detector and an Acton SP2300 monochromator detector with a focal length of 300 mm.

[0108] The cyclic voltammetry was driven by a VersaSTAT 3 from Princeton, USA, and the acquisition time of the electrochemiluminescence spectrum driven by cyclic voltammetry was 64 seconds.

[0109] Example 1

[0110] S 2- Preparation method of stable CdSe / ZnCdS quantum dots:

[0111] (1) 513 mg of CdO, 2.74 g of myristic acid, and 20 mL of octadecene were added sequentially to a three-necked flask. After degassing at room temperature for 15 min, the mixture was heated to 270°C until the CdO was completely dissolved. The mixture was cooled to 90°C, degassed for 1 h, filled with argon, and 20 mL of dry ODE was added. The temperature was raised to 240°C, and 157.9 mg of Se (dissolved in 2 mL of octadecene) was quickly added. The temperature was maintained for 5 min. When the temperature dropped to 180°C, 1 mL of 2-ethylhexanoic acid and 4 mL of oleic acid were added to the reaction system.

[0112] (2) Prepare a mixed solution of zinc 2-ethylhexanoate (2.88 mL) and thiourea (532.2 mg dissolved in 6 mL triethylene glycol dimethyl ether) and slowly inject it into the core layer reaction system three times at 180 ° C. After the shell grows for 10 min, the flask is cooled to room temperature and centrifuged with isopropanol and acetonitrile respectively to obtain CdSe / ZnCdS-S 2- core / shell quantum dots;

[0113] (3) CdSe / ZnCdS-S 2- The hexane solution of core / shell quantum dots was mixed with the NMF solution of (NH4)2S and stirred vigorously. The quantum dots were completely transferred from the upper hexane phase to the lower NMF phase, and the ligand exchange was successful. The NMF phase was washed with hexane five times, collected, and centrifuged with two volumes of acetone to precipitate the quantum dots. The resulting precipitate was redispersed in NMF and filtered through a membrane. The precipitate was vacuum dried at room temperature overnight to obtain S 2- Stable CdSe / ZnCdS quantum dots;

[0114] Product Characterization:

[0115] The S obtained in this example 2- High-magnification transmission electron microscopy images of stable CdSe / ZnCdS quantum dots are shown in Figure 2. Figure 1 As shown by Figure 1 It can be seen that the quantum dots are uniformly spherical and have a narrow particle size distribution with an average particle size of 3.2±0.5nm.

[0116] The S obtained in this example 2- The XPS spectrum of stable CdSe / ZnCdS quantum dots is as follows Figure 2 As shown by Figure 2 It can be seen that quantum dots contain Cd, Se, Zn, and S elements.

[0117] The S obtained in this example 2- XRD patterns of stable CdSe / ZnCdS quantum dots Figure 3 As shown by Figure 3 It can be seen that CdS and ZnS shells are formed on the surface of quantum dots.

[0118] The S obtained in this example 2- The UV absorption of stable CdSe / ZnCdS quantum dots is shown in the figure below. Figure 4 As shown by Figure 4 It can be seen that the characteristic ultraviolet absorption peaks of quantum dots are at 525nm and 580nm.

[0119] The S obtained in this example 2- Stable CdSe / ZnCdS quantum dot fluorescence Figure 4 As shown by Figure 4 It can be seen that the maximum fluorescence emission wavelength of quantum dots is at 610 nm.

[0120] The S obtained in this example 2- The stable CdSe / ZnCdS quantum dot fluorescence lifetime decay curve is as follows Figure 5 As shown by Figure 5 It can be seen that the fluorescence lifetime of quantum dots is 11.75ns.

[0121] Example 2

[0122] S 2- Preparation method of stable CdSe / ZnCdS quantum dot aerogel:

[0123] S 2- Stable CdSe / ZnCdS quantum dots were added to NMF to make S 2- The volume ratio of stable CdSe / ZnCdS quantum dots to NMF is 1:5; a mixed solution is formed, water with a volume ratio of 2% (v / v) of the quantum dots is added to the mixed solution and kept for 2-7 days to induce gelation; the resulting product is washed 20 times with ethanol to remove residues; and a hydrogel is obtained.

[0124] The ethanol solvent dispersed in the CdSe / ZnCdS hydrogel was replaced by CO2 in an autoclave, and supercritical drying was performed at 100 bar and 45°C to prepare the CdSe Aerogel.

[0125] The ultraviolet absorption graph of CdSe Aerogel obtained in this example is shown in FIG. Figure 6 As shown by Figure 6 It can be seen that CdSe Aerogel proves the successful preparation of aerogel structure.

[0126] The ultraviolet absorption graph of CdSe Aerogel obtained in this example is shown in FIG. Figure 7 As shown by Figure 7 It can be seen that the characteristic UV absorption peaks of CdSe Aerogel are at 525nm and 580nm, and the absorption intensity is slightly lower than that of CdSe QDs under the same conditions.

[0127] The fluorescence image of CdSe Aerogel obtained in this example is shown in FIG. Figure 7 As shown by Figure 7 It can be seen that the maximum fluorescence emission wavelength of CdSe Aerogel is located at 610 nm.

[0128] The CdSe Aerogel fluorescence lifetime decay curve obtained in this example is as follows: Figure 8 As shown by Figure 8 It can be seen that the fluorescence lifetime of CdSeAerogel is 17.40 ns.

[0129] The reduced fluorescence intensity and prolonged exciton lifetime of CdSe Aerogel are attributed to the delocalization of excited electrons in the aerogel network due to fusion-based electronic coupling between QDs.

[0130] Example 3

[0131] The CdSe Aerogel prepared in Example 2 was diluted to a 0.5 mg / mL monodisperse solution. 5 μL of 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M borate buffer solution (pH 7.4). Anodic differential pulse voltammetry was performed using a platinum wire as the counter electrode and an Ag / AgCl electrode as the reference electrode.

[0132] The differential pulse voltammetry curve of the CdSe Aerogel anode obtained in this example is as follows: Figure 9 As shown by Figure 9 It can be seen that the oxidation current signal generated by CdSe Aerogel at 1.16V is greatly enhanced.

[0133] Example 4

[0134] Construction of anode co-reactant type electrochemiluminescence system:

[0135] The CdSe Aerogel prepared in Example 2 was diluted to a monodisperse solution of 0.5 mg / mL. 5 μL of 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M borate buffer solution (pH 7.4). Cyclic voltammetry was performed using a platinum wire as the counter electrode, an Ag / AgCl electrode as the reference electrode, and 10 mM triethanolamine as the co-reactant.

[0136] Cyclic voltammetry was used for driving, with a potential window of 0 to 1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward the positive direction. The obtained electrochemiluminescence intensity-(potential) time curve is shown in FIG. Figure 10 As shown, Figure 10It can be seen that the anode co-reactant type electrochemiluminescence system of the present invention can generate oxidation-reduction electrochemiluminescence at 1.20V in 0.1M pH=7.4 borate buffer solution, and its electrochemiluminescence signal intensity is enhanced 126 times compared with CdSe QDs.

[0137] Cyclic voltammetry was used, with a potential window of 0 to 1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan in the positive direction. The anodic electrochemiluminescence spectrum was obtained as follows: Figure 11 As shown, Figure 11 It can be seen that the anode co-reactant type electrochemiluminescence system of the present invention can generate an electrochemiluminescence signal with a maximum emission wavelength at 610 nm in a 0.1 M pH = 7.4 borate buffer solution, and its electrochemiluminescence signal intensity is enhanced 126 times compared with CdSe QDs.

[0138] Cyclic voltammetry was used, with a potential window of 0 to 1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan in the positive direction. The obtained anodic Spooling electrochemiluminescence spectrum was as follows: Figure 12 As shown, Figure 12 It can be seen that the electrochemiluminescence signal intensity of the anode co-reactant type electrochemiluminescence system of the present invention corresponds to 1.20V at a maximum emission wavelength of 610nm in a 0.1M borate buffer solution with a pH of 7.4.

[0139] Example 5

[0140] Construction of cathode co-reactant type electrochemiluminescence system:

[0141] The CdSe Aerogel prepared in Example 2 was diluted to a 0.5 mg / mL monodisperse solution. 5 μL of the 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M borate buffer solution (pH 7.4). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry was performed.

[0142] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 13 As shown, Figure 13 It can be seen that the cathode co-reactant type electrochemiluminescent system of the present invention can generate an electrochemiluminescent signal with a maximum emission wavelength at 610 nm in a 0.1 M borate buffer solution with a pH of 7.4.

[0143] Example 6

[0144] Construction of cathode co-reactant type electrochemiluminescence system:

[0145] The CdSe Aerogel prepared in Example 2 was diluted to a 0.5 mg / mL monodisperse solution. 5 μL of 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M acetate buffer solution (pH 6.4). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry was performed.

[0146] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 14 As shown, Figure 14 It can be seen that the cathode co-reactant type electrochemiluminescent system of the present invention can generate an electrochemiluminescent signal with a maximum emission wavelength at 610 nm in a 0.1 M acetate buffer solution with a pH of 6.4.

[0147] Example 7

[0148] Construction of cathode co-reactant type electrochemiluminescence system:

[0149] The CdSe Aerogel prepared in Example 2 was diluted to a 0.5 mg / mL monodisperse solution. 5 μL of 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M carbonate buffer solution (pH 9.0). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as the co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0150] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 15 As shown, Figure 15 It can be seen that the electrochemiluminescent material prepared in Example 2 of the present invention can generate an electrochemiluminescent signal with a maximum emission wavelength at 610 nm in a 0.1 M carbonate buffer solution with a pH of 9.0.

[0151] Example 8

[0152] Construction of cathode co-reactant type electrochemiluminescence system:

[0153] The CdSe Aerogel prepared in Example 2 was diluted to a 0.5 mg / mL monodisperse solution. 5 μL of 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M phosphate buffer solution (pH 7.4). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0154] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 16 As shown, Figure 16 It can be seen that the cathode co-reactant type electrochemiluminescent system of the present invention can generate an electrochemiluminescent signal with a maximum emission wavelength at 610 nm in a 0.1 M phosphate buffer solution with a pH of 7.4.

[0155] Example 9

[0156] Construction of cathode co-reactant type electrochemiluminescence system:

[0157] The CdSe Aerogel prepared in Example 2 was diluted to a monodisperse solution of 0.5 mg / mL. 5 μL of 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M Tris-HCl buffer solution (pH 7.4). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0158] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 17 As shown, Figure 17 It can be seen that the cathode co-reactant type electrochemiluminescent system of the present invention can generate an electrochemiluminescent signal with a maximum emission wavelength at 610 nm in a 0.1 M pH=7.4 Tris-HCl buffer solution.

[0159] Example 10

[0160] Construction of annihilation-type electrochemiluminescence system:

[0161] The CdSe Aerogel prepared in Example 2 was diluted to a monodisperse solution of 0.5 mg / mL. 5 μL of 0.5 mg / mL CdSe Aerogel was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M pH 7.4 borate buffer solution. A platinum wire was used as the counter electrode and an Ag / AgCl electrode was used as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0162] Cyclic voltammetry was used, with a potential window of -1.4 to 1.4 V, a scan rate of 200 mV / s, a starting potential of 0 V, and an initial scan toward positive. The electrochemiluminescence intensity-potential curve was as follows: Figure 18 As shown, Figure 18 It can be seen that the annihilation-type electrochemiluminescence system of the present invention can produce strong electrochemiluminescence at the cathode and anode respectively in 0.1 M pH = 7.4 borate buffer solution. Its cathode electrochemiluminescence signal is enhanced by 1.5 times compared with CdSe QDs under the same conditions, and its anode electrochemiluminescence signal is enhanced by 13 times compared with CdSe QDs under the same conditions.

[0163] Cyclic voltammetry was used, with a potential window of -1.4 to 1.4 V, a scan rate of 200 mV / s, a starting potential of 0 V, and an initial scan toward negative. The electrochemiluminescence intensity-potential curve was as follows: Figure 19 As shown, Figure 19 It can be seen that the annihilation-type electrochemiluminescence system of the present invention can produce strong electrochemiluminescence at the cathode and anode respectively in 0.1 M pH = 7.4 borate buffer solution. Its cathode electrochemiluminescence signal is enhanced by 1.5 times compared with CdSe QDs under the same conditions, and its anode electrochemiluminescence signal is enhanced by 15 times compared with CdSe QDs under the same conditions.

[0164] Comparative Example 1

[0165] The method described in Example 3 is the same as that described in Example 3, except that:

[0166] The luminescent reagent CdSe Aerogel was removed.

[0167] A bare gold electrode was placed in 4 mL of 0.1 M borate buffer solution with a pH of 7.4, a platinum wire was used as the counter electrode, and an Ag / AgCl electrode was used as the reference electrode to measure the anodic differential pulse voltammetry curve.

[0168] The anodic differential pulse voltammetry curve obtained in this comparative example is as follows: Figure 20 As shown by Figure 20 It can be seen that the bare gold electrode cannot generate an oxidation current signal in a 0.1 M borate buffer solution with a pH of 7.4.

[0169] Comparative Example 2

[0170] The same construction method as described in Example 4 is different in that:

[0171] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M borate buffer solution (pH = 7.4). A platinum wire was used as the counter electrode and an Ag / AgCl electrode was used as the reference electrode to measure the differential pulse voltammetry curve of the anode.

[0172] The differential pulse voltammetry curve of the anode of CdSe QDs obtained in this comparative example is as follows: Figure 21 As shown by Figure 21 It can be seen that the oxidation current signal of CdSe QDs at 1.16V is significantly smaller than that of Example 3.

[0173] Combining Comparative Example 2 and Example 3, it can be seen that the efficiency of hole injection into aerogel VB is higher. This is because the electronic coupling between adjacent QDs in the 3D network structure provides an effective electron tunneling path.

[0174] Comparative Example 3

[0175] The same construction method as described in Example 4 is different in that:

[0176] The luminescent reagent CdSe Aerogel was removed.

[0177] A bare gold electrode was placed in 4 mL of 0.1 M pH = 7.4 borate buffer solution containing 10 mM triethanolamine, and a platinum wire was used as a counter electrode and an Ag / AgCl electrode was used as a reference electrode to perform cyclic voltammetry scanning.

[0178] Cyclic voltammetry was used for driving, with a potential window of 0 to 1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward the positive direction. The electrochemiluminescence intensity-(potential) time curve was as follows: Figure 22 As shown, Figure 22 It can be seen that the bare gold electrode cannot generate an electrochemiluminescence signal of the anodic co-reactant in a 0.1 M pH=7.4 borate buffer solution containing 10 mM triethanolamine.

[0179] From Comparative Examples 2 and 3 as well as Examples 3 and 4, it can be seen that the high-intensity electrochemiluminescence system is based on CdSe Aerogel, while CdSe QDs or CdSe Aerogel without luminescent reagent cannot produce high-intensity electrochemiluminescence.

[0180] Comparative Example 4

[0181] The same construction method as described in Example 4 is different in that:

[0182] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M borate buffer solution (pH = 7.4). Cyclic voltammetry was performed using a platinum wire as the counter electrode, an Ag / AgCl electrode as the reference electrode, and 10 mM triethanolamine as the co-reactant.

[0183] Cyclic voltammetry was used for driving, with a potential window of 0 to 1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward the positive direction. The electrochemiluminescence intensity-(potential) time curve was as follows: Figure 23 As shown, Figure 23 It can be seen that the electrochemiluminescence system can generate oxidation-reduction electrochemiluminescence at 1.20 V in a 0.1 M borate buffer solution with a pH of 7.4, but the electrochemiluminescence signal intensity is significantly lower than that of Example 4.

[0184] Cyclic voltammetry was used, with a potential window of 0 to 1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan in the positive direction. The anodic electrochemiluminescence spectrum was obtained as follows: Figure 24 As shown, Figure 24 It can be seen that the electrochemiluminescence system can generate an electrochemiluminescence signal with a maximum emission wavelength at 610 nm in a 0.1 M borate buffer solution with a pH of 7.4, but the electrochemiluminescence signal intensity is significantly lower than that of Example 4.

[0185] Cyclic voltammetry was used, with a potential window of 0 to 1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan in the positive direction. The obtained anodic Spooling electrochemiluminescence spectrum was as follows: Figure 25 As shown, Figure 25 It can be seen that in the electrochemiluminescence system in a 0.1 M borate buffer solution with a pH of 7.4, the electrochemiluminescence signal with a maximum emission wavelength at 610 nm corresponds to 1.20 V.

[0186] Combining Comparative Example 4 and Example 4, under the same conditions, the anodic electrochemiluminescence signal of CdSe Aerogel is greatly enhanced relative to that of CdSe QDs, which is attributed to the specific structure of the aerogel. For the aerogel structure, QDs far away from the electrode surface can still be effectively oxidized. In contrast, CdSe QDs, due to the presence of an interfacial charge transfer barrier, can only inject holes into QDs in contact with the electrode, resulting in a low electrochemiluminescence efficiency of QDs. In summary, the aerogel form can greatly enhance the anodic electrochemiluminescence of the co-reactant form of quantum dots.

[0187] Comparative Example 5

[0188] The same construction method as described in Example 5, except that:

[0189] The luminescent reagent CdSe Aerogel was removed.

[0190] A bare gold electrode was placed in 4 mL of 0.1 M pH 7.4 borate buffer solution containing 10 mM ammonium persulfate, with a platinum wire as the counter electrode and an Ag / AgCl electrode as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0191] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 26 As shown, Figure 26 It can be seen that the bare gold electrode cannot generate cathode co-reactant type electrochemiluminescence signal in 0.1 M pH = 7.4 borate buffer solution containing 10 mM ammonium persulfate.

[0192] Comparative Example 6

[0193] The same construction method as described in Example 5, except that:

[0194] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M borate buffer solution (pH 7.4). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0195] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 27 As shown, Figure 27It can be seen that the electrochemiluminescence system can generate an electrochemiluminescence signal with a maximum emission wavelength at 610 nm in a 0.1 M borate buffer solution with a pH of 7.4, but the electrochemiluminescence signal intensity is significantly lower than that in Example 5.

[0196] Combining Comparative Example 6 and Example 5, under the same conditions, the electrochemiluminescence signal of CdSe Aerogel is enhanced 56 times relative to that of CdSe QDs.

[0197] Comparative Example 7

[0198] The same construction method as described in Example 6, except that:

[0199] The luminescent reagent CdSe Aerogel was removed.

[0200] A bare gold electrode was placed in 4 mL of 0.1 M acetate buffer solution (pH 6.4) containing 10 mM ammonium persulfate, with a platinum wire as the counter electrode and an Ag / AgCl electrode as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0201] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 28 As shown, Figure 28 It can be seen that the bare gold electrode cannot generate cathode co-reactant type electrochemiluminescence signal in 0.1M acetate buffer solution with pH=7.4 containing 10 mM ammonium persulfate.

[0202] Comparative Example 8

[0203] The same construction method as described in Example 6, except that:

[0204] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M acetate buffer solution with a pH of 6.4. A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0205] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 29 As shown, Figure 29It can be seen that the electrochemiluminescence system can generate an electrochemiluminescence signal with a maximum emission wavelength at 610 nm in a 0.1 M acetate buffer solution with a pH of 6.4, but the electrochemiluminescence signal intensity is significantly lower than that of Example 6.

[0206] Combining Comparative Example 8 and Example 6, under the same conditions, the electrochemiluminescence signal of CdSe Aerogel is enhanced 95 times relative to that of CdSe QDs.

[0207] Comparative Example 9

[0208] The same construction method as described in Example 7, except that:

[0209] The luminescent reagent CdSe Aerogel was removed.

[0210] A bare gold electrode was placed in 4 mL of 0.1 M pH 9.0 carbonate buffer solution containing 10 mM ammonium persulfate, with a platinum wire as the counter electrode and an Ag / AgCl electrode as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0211] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 30 As shown, Figure 30 It can be seen that the bare gold electrode cannot generate cathode co-reactant type electrochemiluminescence signal in 0.1M pH=9.0 carbonate buffer solution containing 10 mM ammonium persulfate.

[0212] Comparative Example 10

[0213] The same construction method as described in Example 7, except that:

[0214] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M carbonate buffer solution (pH 9.0). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as the co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0215] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 31 As shown, Figure 31It can be seen that the electrochemiluminescence system can generate an electrochemiluminescence signal with a maximum emission wavelength at 610 nm in a 0.1 M carbonate buffer solution with a pH of 9.0, but the electrochemiluminescence signal intensity is significantly lower than that in Example 7.

[0216] Combining Comparative Example 10 and Example 7, under the same conditions, the electrochemiluminescence signal of CdSe Aerogel is enhanced 116 times relative to that of CdSe QDs.

[0217] Comparative Example 11

[0218] The same construction method as described in Example 8, except that:

[0219] The luminescent reagent CdSe Aerogel was removed.

[0220] A bare gold electrode was placed in 4 mL of 0.1 M pH 7.4 phosphate buffer solution containing 10 mM ammonium persulfate, with a platinum wire as the counter electrode and an Ag / AgCl electrode as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0221] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 32 As shown, Figure 32 It can be seen that the bare gold electrode cannot generate cathode co-reactant type electrochemiluminescence signal in 0.1M pH=7.4 phosphate buffer solution containing 10 mM ammonium persulfate.

[0222] Comparative Example 12

[0223] The same construction method as described in Example 8, except that:

[0224] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M phosphate buffer solution (pH 7.4). A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0225] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 33 As shown, Figure 33It can be seen that the electrochemiluminescence system can generate an electrochemiluminescence signal with a maximum emission wavelength at 610 nm in a 0.1 M phosphate buffer solution with a pH of 7.4, but the electrochemiluminescence signal intensity is significantly lower than that of Example 8.

[0226] Combining Comparative Example 12 and Example 8, under the same conditions, the electrochemiluminescence signal of CdSe Aerogel is enhanced 23 times relative to that of CdSe QDs.

[0227] Comparative Example 13

[0228] The same construction method as described in Example 9, except that:

[0229] The luminescent reagent CdSe Aerogel was removed.

[0230] A bare gold electrode was placed in 4 mL of 0.1 M Tris-HCl buffer solution (pH = 7.4) containing 10 mM ammonium persulfate. A platinum wire was used as the counter electrode and an Ag / AgCl electrode was used as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0231] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 34 As shown, Figure 34 It can be seen that the bare gold electrode cannot generate cathode co-reactant type electrochemiluminescence signal in 0.1M Tris-HCl buffer solution with pH=7.4 containing 10 mM ammonium persulfate.

[0232] Comparative Example 14

[0233] The same construction method as described in Example 9, except that:

[0234] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M pH = 7.4 Tris-HCl buffer solution. A platinum wire was used as the counter electrode, an Ag / AgCl electrode was used as the reference electrode, and 10 mM ammonium persulfate was used as a co-reactant. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0235] Cyclic voltammetry was used, with a potential window of 0 to -1.6 V, a scan rate of 100 mV / s, a starting potential of 0 V, and an initial scan toward negative. The cathode electrochemiluminescence spectrum obtained was as follows: Figure 35 As shown, Figure 35It can be seen that the electrochemiluminescence system can generate an electrochemiluminescence signal with a maximum emission wavelength at 610 nm in a 0.1 M pH=7.4 Tris-HCl buffer solution, but the electrochemiluminescence signal intensity is significantly lower than that of Example 9.

[0236] Combining Comparative Example 14 and Example 9, under the same conditions, the electrochemiluminescence signal of CdSe Aerogel is enhanced 60 times relative to that of CdSe QDs.

[0237] Based on Comparative Examples 6, 8, 10, 12, 14 and Examples 5 to 9, the electrochemiluminescence signals of CdSe Aerogel in various buffer solutions containing ammonium persulfate (including 0.1M borate with pH = 7.4, 0.1M acetate with pH = 6.4, 0.1M carbonate with pH = 9.0, 0.1M phosphate with pH = 7.4, and 0.1M Tris-HCl buffer with pH = 7.4) all showed varying degrees of enhancement relative to CdSe QDs. This demonstrates that the aerogel form can effectively enhance the cathode electrochemiluminescence of the co-reactant form of quantum dots.

[0238] Comparative Example 15

[0239] The same construction method as described in Example 10, except that:

[0240] The luminescent reagent CdSe Aerogel was removed.

[0241] A bare gold electrode was placed in 4 mL of 0.1 M borate buffer solution (pH = 7.4), with a platinum wire as the counter electrode and an Ag / AgCl electrode as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0242] Cyclic voltammetry was used, with a potential window of -1.4 to 1.4 V, a scan rate of 200 mV / s, a starting potential of 0 V, and an initial scan toward positive. The electrochemiluminescence intensity-potential curve was as follows: Figure 36 As shown, Figure 36 It can be seen that the bare gold electrode cannot generate annihilation-type (cathode and anode) electrochemiluminescence signals in a 0.1 M borate buffer solution with a pH of 7.4.

[0243] The electrochemical luminescence intensity-potential curve obtained by cyclic voltammetry was as follows: Figure 37 As shown, Figure 37 It can be seen that the bare gold electrode cannot generate annihilation-type (cathode and anode) electrochemiluminescence signals in a 0.1 M borate buffer solution with a pH of 7.4.

[0244] Comparative Example 16

[0245] The same construction method as described in Example 10, except that:

[0246] The CdSe Aerogel was replaced with CdSe QDs of the same concentration, and 5 μL of 0.5 mg / mL CdSe QDs was drop-coated on a bare gold electrode. The dried electrode was placed in 4 mL of 0.1 M pH = 7.4 borate buffer solution. A platinum wire was used as the counter electrode and an Ag / AgCl electrode was used as the reference electrode. After nitrogen flow was passed through the solution for 15 minutes, cyclic voltammetry scanning was performed.

[0247] Cyclic voltammetry was used for driving, with a potential window of -1.4 to 1.4 V, a scan rate of 200 mV / s, a starting potential of 0 V, and an initial scan toward the positive direction. The annihilation-type electrochemiluminescence-potential curve was obtained as shown below: Figure 38 As shown, Figure 38 It can be seen that the electrochemiluminescence system can generate weak electrochemiluminescence at the anode and cathode respectively in a 0.1 M pH=7.4 borate buffer solution, and the electrochemiluminescence signal intensity is less than that of Example 10.

[0248] Cyclic voltammetry was used for driving, with a potential window of -1.4 to 1.4 V, a scan rate of 200 mV / s, a starting potential of 0 V, and an initial scan toward negative. The annihilation-type electrochemiluminescence-potential curve was obtained as shown below: Figure 39 As shown, Figure 39 It can be seen that the electrochemiluminescence system of the present invention can generate weak electrochemiluminescence at the anode and cathode respectively in 0.1 M pH=7.4 borate buffer solution, and the electrochemiluminescence signal intensity is less than that of Example 10.

[0249] Based on Comparative Example 16 and Example 10, the annihilation-type (cathode and anode) electrochemiluminescence signals of CdSe Aerogel in 0.1M borate buffer solution with a pH of 7.4 showed varying degrees of enhancement compared to CdSe QDs, demonstrating that the aerogel form can effectively enhance the annihilation-type electrochemiluminescence of quantum dots.

Claims

1. An electrochemiluminescence system based on aerogel enhancement, using S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent reagent to form a co-reactant or annihilation type electrochemiluminescence system in the presence of a buffer solution; CdSe / ZnCdS-S 2- The volume ratio of core / shell quantum dots to hexane is (1-2): (1-2), the concentration of (NH4)2S in the NMF solution is 3-7mM; CdSe / ZnCdS-S 2- The volume ratio of the hexane solution of core / shell quantum dots to the NMF solution of (NH4)2S was 1:5; For the co-reactant type electrochemiluminescence system, At the anode, S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent agent, triethanolamine is used as an anode co-reactant, and borate is used as a buffer solution to form an anode co-reactant type electrochemiluminescence system. At the cathode, S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent agent, ammonium persulfate is used as a cathode co-reactant, and one of borate, acetate, carbonate, phosphate or Tris-HCl is used as a buffer solution to form a cathode co-reactant type electrochemiluminescence system; S 2- The specific preparation method of stable CdSe / ZnCdS quantum dot aerogel is as follows: (1) 4 mmol CdO, 12 mmol myristic acid and 20 mL 1-octadecene were mixed evenly and degassed at room temperature for 15 min. After the reaction apparatus was filled with argon, the mixture was heated to 270 °C until the CdO was completely dissolved; the mixture was cooled to 90 °C and degassed at 90 °C for 1 h. After filling with argon, 20 mL dry 1-octadecene was added and degassed at 80 °C for 1 h. After degassed, the temperature was raised to 240 °C and the Se 1-octadecene suspension was quickly added. The temperature was maintained at 240 °C for 5 min to achieve the growth of CdSe quantum dot cores. After the growth was completed, the temperature was lowered to 180 °C and 1 mL 2-ethylhexanoic acid and 4 mL oleic acid were added to the reaction system; (2) 7 mmol of thiourea was dissolved in 6 mL of triethylene glycol dimethyl ether, and 2.88 mL of zinc 2-ethylhexanoate was added. The resulting mixed solution was divided into three equal parts; it was slowly injected into the system obtained in step (1) three times at 180°C for 10 min of shell growth. After cooling to room temperature, the system was centrifuged with isopropanol and acetonitrile respectively to obtain CdSe / ZnCdS-S 2- core / shell quantum dots; (3) CdSe / ZnCdS-S 2- The hexane solution of core / shell quantum dots was mixed with the NMF solution of (NH4)2S and stirred vigorously. The quantum dots were completely transferred from the upper hexane phase to the lower NMF phase, indicating successful ligand exchange. The NMF phase was washed 5-8 times with hexane, collected, and centrifuged with twice the volume of acetone to precipitate the quantum dots. The resulting precipitate was redispersed in NMF and filtered through a membrane. The precipitate was vacuum dried at room temperature overnight to obtain S 2- Stable CdSe / ZnCdS quantum dots; (4) S 2- Stable CdSe / ZnCdS quantum dots are added to a NMF solution to form a mixed solution. Water (1.5-2.5% v / v by volume of the quantum dots) is added to the mixed solution and maintained for 2-7 days for gelation to obtain a hydrogel. The obtained hydrogel is washed with ethanol 20-30 times to remove residues. The ethanol is replaced with liquid carbon dioxide and supercritical drying is performed to produce an aerogel.

2. The electrochemiluminescence system according to claim 1, characterized in that S 2- The concentration of stable CdSe / ZnCdS quantum dot aerogel is 0.1-1 mg / mL.

3. The electrochemiluminescence system according to claim 1, characterized in that In the co-reactant type electrochemiluminescence system, the pH of the borate buffer, phosphate buffer, and Tris-HCl buffer is 7.0-7.4; Carbonate buffer pH = 8.8-9.4; Acetate buffer pH = 6.0-6.6; The concentration of the buffer solution is 0.05-0.5 M; The concentration of the co-reactant was 8-12 mM.

4. The electrochemiluminescence system according to claim 1, characterized in that For annihilation-type electrochemiluminescence systems, S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent reagent, and borate is used as a buffer solution to form an annihilation-type electrochemiluminescence system; the concentration of the borate buffer solution is 0.05-0.5 M.

5. The method for constructing the electrochemiluminescence system according to any one of claims 1 to 4, comprising the following steps: For the co-reactant type electrochemiluminescence system, S 2- Stable CdSe / ZnCdS quantum dot aerogel is used as a luminescent reagent, triethanolamine or ammonium persulfate is used as a co-reactant, and a co-reactant type electrochemiluminescence system is formed in the presence of a buffer solution. The electrochemiluminescence radiation of the co-reactant type electrochemiluminescence system was driven by a three-electrode system and cyclic voltammetry scanning method; For annihilation-type electrochemiluminescence system, S 2- Stable CdSe / ZnCdS quantum dot aerogel CdSe Aerogel is used as a luminescent reagent, and in the presence of a buffer solution, a co-reactant type electrochemiluminescence system is formed; A three-electrode system and a cyclic voltammetry scanning method are used to apply a voltage with an initial positive or negative sweep to drive the annihilation-type electrochemiluminescence system to emit electrochemiluminescence.

6. The construction method according to claim 5, characterized in that: The electrochemical conditions adopted are: a gold electrode drop-coated with a luminescent reagent is used as the working electrode, a platinum wire is used as the counter electrode, and an Ag / AgCl electrode is used as the reference electrode, and cyclic voltammetry scans are performed in a buffer solution containing / not containing a co-reactant; when performing cyclic voltammetry scans, the scanning voltage range is -1.6 to 1.6 V, the number of scans is 1 to 3, and the scanning speed is 100 to 200 mV / s.

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