Signal-enhanced electrochemical luminescence sensing method for rapidly detecting fumonisins B1

Abstract

The invention relates to the technical field of electrochemical luminescence analysis, in particular to a signal enhancement type material for rapidly detecting fumonisins B1 and a preparation method and application of an electrochemical luminescence sensor of the signal enhancement type material. The invention provides a novel signal amplification strategy for solving the problems of expensive instruments, complicated operation or insufficient sensitivity and the like in the existing fumonisins B1 detection method. The core lies in that an efficient ternary electrochemical luminescence system is constructed, three-dimensional perovskite quantum dots of a core-shell structure and silicon dioxide serve as stable luminous bodies, tripropylamine serves as a co-reaction agent, and niobium-doped copper bismuthate loaded gold nanoparticles are innovatively introduced to serve as a composite co-reaction accelerant. The accelerant plays dual functions: niobium-doped copper bismuthate is used as a p-type semiconductor, the conductivity is improved through niobium doping, and the oxidation process of tripropylamine is efficiently catalyzed; the gold nanoparticles loaded on the surface greatly enhance the electrochemical luminescence intensity of the three-dimensional perovskite quantum dot and silicon dioxide core-shell structure through a local surface plasma resonance effect. And through the synergistic effect of the two, obvious amplification of an electrochemical luminescence signal is realized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of analytical chemistry and biosensing technology, and particularly relates to a novel electrochemiluminescence (ECL) detection system and application thereof. Specifically, the present application provides a high-performance ECL sensing platform based on Nb:CuBi2O4@Au NPs as a co-reaction promoter, SiO2@CsPbBr3 as a luminescent body, and tripropylamine as a co-reaction agent, and further discloses an immunoassay method for detecting mycotoxins, particularly fumonisin B1, using the platform. The present application solves the problems of poor ECL stability and insufficient signal intensity of perovskite materials in the prior art, and provides an innovative solution for high-sensitivity and high-stability biomolecule detection. BACKGROUND

[0002] Fumonisin B1, as a highly effective, broad-spectrum, and systemic neonicotinoid insecticide, is widely used in agriculture (vegetables, fruits, grains, cotton, tea, etc.), horticulture (flowers, ornamental plants), and forestry for controlling piercing-sucking mouthpart pests (such as aphids, whiteflies, leafhoppers, thrips, and planthoppers). Due to its good effect and relatively low acute toxicity to mammals, it is used in large quantities worldwide. After fumonisin is applied to crops, it or its metabolites may remain in agricultural products (fruits, vegetables, grains, tea, etc.) and the environment (soil, water). However, excessive fumonisin residues in agricultural products may enter the human body through the food chain, posing a potential threat to human health. Although the acute toxicity is low, long-term low-dose intake may have adverse effects on the nervous system, reproductive system, and other potential risks such as endocrine disruption. Especially for infants and sensitive groups, the risk is higher. Fumonisin B1 has high toxicity to non-target organisms, especially pollinating insects (such as bees) and aquatic organisms (such as fish and crustaceans). Its residues entering water bodies or soil can disrupt the ecological balance and threaten biodiversity. The reduction of beneficial insects such as bees has a profound impact on agricultural production and the ecosystem. Long-term and large-scale use may lead to the development of pesticide resistance in pests. The research, development, standardization, and application of fumonisin B1 detection technology are essential for food safety control, environmental protection, and sustainable agricultural development.

[0003] Electrochemiluminescence aptamer sensor combines the ultra-high sensitivity of electrochemiluminescence with the high specificity and easy modification of aptamer, uses aptamer as a molecular recognition element, and at the same time, the electrochemiluminescence signal is generated on the electrode surface, with extremely low background noise, providing detection sensitivity much higher than traditional optical methods (up to trace / ultra-trace level); the technology is usually simple in operation, fast in analysis, easy to realize miniaturization and automation, and has the potential for rapid on-site screening; in addition, aptamer is easy to design and label, which is convenient for constructing multifunctional sensing interface, and also provides the possibility for simultaneous detection of multiple target substances (such as fumonisin B1 and its metabolites), which is an ideal platform to meet the modern high-sensitivity, high-specificity, rapid and convenient detection requirements. Electrochemiluminescence aptamer sensor has been widely used in biological analysis, food detection, environmental protection and other fields. For example, in environmental detection, it can be used for harmful substances such as environmental estrogens and heavy metal ions; in biological analysis, it can be used for detecting cancer markers, disease-related proteins and other biomarkers.

[0004] Therefore, it is of urgent practical need and important application value to develop a high-performance electrochemiluminescence sensor based on a new type of nanomaterial and signal amplification strategy to realize rapid and ultra-sensitive detection of fumonisin B1 in food. SUMMARY

[0005] In the prior art, electrochemiluminescence methods for detecting small molecule toxins such as fumonisin B1 usually rely on traditional luminophores, which have limited luminescence efficiency. At the same time, directly using perovskite quantum dots as luminophores faces the problems of poor water stability and easy quenching. In addition, the traditional co-reaction promotion system has the disadvantages of insufficient signal amplification ability and poor stability, which limits the further improvement of the sensitivity and reliability of the sensor. Therefore, there is an urgent need to develop a new ECL sensing platform with high stability, high intensity luminescence signal and excellent sensitivity.

[0006] One of the purposes of the present application is to prepare a Nb:CuBi2O4@Au NPs to solve the problem of insufficient catalytic activity or signal enhancement ability of a single material, which has excellent electrocatalytic activity of Nb:CuBi2O4 and plasmonic resonance effect of Au NPs, and can synergistically amplify the ECL signal.

[0007] The second purpose of the present application is to prepare a SiO2@CsPbBr3 with core-shell structure, which effectively protects the CsPbBr3 core from water and oxygen by the inert and dense SiO2 shell, and solves the problem of application stability of perovskite nanocrystals in biological analysis system.

[0008] The third object of the application is to organically combine Nb: CuBi2O4@ Au NPs, SiO2@ CsPbBr3 and tripropylamine co-reagent, and construct a stable, efficient and signal intensity significantly enhanced ternary ECL detection system.

[0009] The fourth object of the application is to construct a sensor based on the ECL system for quantitative detection of fumonisin B1, which has an extremely low detection limit, a wide linear range and good specificity.

[0010] The fifth object of the application is to construct a simple and low-cost fumonisin B1 immunodetection method. The method fixes the fumonisin B1 aptamer on the electrode modified with the ECL system, and realizes rapid and accurate analysis of fumonisin B1 in actual samples by using the quenching effect of ECL signal after specific binding.

[0011] 1. An electrochemiluminescence sensing method for rapid detection of fumonisin B1 with signal enhancement, characterized by comprising the following steps: (1) Preparation of Nb-doped copper bismuthate loaded gold nanoparticles Nb: CuBi2O4@ Au NPs Weigh 2.5 ~ 12.5 mg of copper nitrate pentahydrate Cu(NO3)2·5H2O, 9.7 ~ 48.5 mg of bismuth nitrate pentahydrate Bi(NO3)3·5H2O and 0.054 ~ 0.27 mg of niobium oxalate C 10 H5NbO 20, dissolve in 5 ~ 10 mL of 2 M dilute nitric acid, magnetic stirring until completely clear, under vigorous stirring, to the solution dropwise addition of 4 M sodium hydroxide solution until the pH value of the solution to 10 ~ 12, in the process, will be observed to the solution gradually changed to dark and produce a large amount of precipitate, the mixed suspension is transferred to a polytetrafluoroethylene lined autoclave, filling degree control in 70% ~ 80%, seal the reactor, it is placed in a forced air drying oven, at 160 ~ 180 °C for 12 ~ 24 hours, after the reaction, natural cooling to room temperature, open the reactor, the reaction product is transferred to the centrifuge tube, with deionized water and anhydrous ethanol alternately centrifugal washing at least 3 times, until the supernatant is neutral, the collected precipitate is placed in a vacuum drying oven, at 60 ~ 80 °C drying 6 ~ 12 hours, get dark brown Nb: CuBi2O4 powder, in order to obtain better crystallinity, the dried powder in the muffle furnace annealing treatment, at 400 ~ 500 °C calcination 2 hours; weigh 30 ~ 70 mg Nb: CuBi2O4 powder, dispersed in 100 mL deionized water, ultrasonic treatment for 30 minutes, so that it is fully dispersed, form a uniform suspension, the suspension is placed in a round bottom flask, heated to boiling under magnetic stirring, quickly add 150 ~ 350 μL of 1 wt% chloroauric acid solution, keep boiling and stirring, quickly add 11.4 ~ 26.6 mg of trisodium citrate solution, continue to reflux reaction 30 ~ 60 minutes, can be observed from the initial dark brown solution gradually changed to purple black or gray black, which indicates that the gold nanoparticles have been successfully generated and loaded on the surface of Nb: CuBi2O4, stop heating, let the reaction system naturally cool to room temperature, the reaction product is washed with deionized water several times to remove unreacted reagents and free gold nanoparticles, the final product in a vacuum drying oven at 50 ~ 60 °C drying 6 ~ 12 hours, the final Nb: CuBi2O4@Au NPs can be obtained.

[0012] (2) Preparation of three-dimensional perovskite quantum dots and silica core-shell structure SiO2@CsPbBr3 weigh 73.4 ~ 146.8 mg of lead bromide and 42.6 ~ 85.1 mg of cesium bromide, placed in a sample bottle, add 5 ~ 10 mL of N, N-dimethylformamide, stirring to completely dissolved, sequentially add 0.5 ~ 1.0 mL of oleic acid and 0.5 ~ 1.0 mL of oleylamine, these ligands can be with Pb 2+The CsPbBr3 precursor solution needs to be prepared immediately before use; in a round-bottom flask equipped with a magnetic stirrer, 20 ~ 30 mL of cyclohexane, 5 ~ 10 mL of Triton X-100, and 5 ~ 10 mL of n-hexanol are sequentially added, and the mixture is stirred vigorously at room temperature for 10-20 minutes to ensure uniform mixing, obtaining an oil phase mixture; 100 ~ 200 µL of the CsPbBr3 precursor solution is taken and added dropwise to the oil phase mixture, and the stirring is continued for 30 minutes, at which time a clear and transparent reverse microemulsion is formed, and the CsPbBr3 precursor is encapsulated in the "water core" of the microemulsion; 200 ~ 400 µL of tetraethyl orthosilicate is added to the microemulsion as a precursor for the SiO2 shell, and 100 ~ 200 µL of ammonia is added as a catalyst for the hydrolysis and condensation of tetraethyl orthosilicate, and the reaction system is sealed and stirred slowly at room temperature for 12-24 hours; after the reaction is completed, an equal volume of acetone is added to the reaction solution to destroy the microemulsion system, and the product is precipitated, the mixture is transferred to a centrifuge tube, and centrifuged at 8000-10000 rpm for 5-10 minutes, and the precipitate is collected, and in order to completely remove the surfactant, unreacted reagents and by-products, the precipitate is washed with ethanol / acetone mixture at a volume ratio of 1:1 or alternatively with ethanol and acetone, and the final light green precipitate is dried in a vacuum drying oven at 40-50 °C for 4-6 hours, and the final product is a light green powder which should be stored in a sealed container at 4 °C to prevent degradation.

[0013] (3) Preparation of three-dimensional perovskite quantum dots and SiO2@CsPbBr3-DNA2 hybrid with core-shell structure 200 ~ 400 mg of SiO2@CsPbBr3 nanoparticles are dispersed in anhydrous toluene or ethanol, 100 ~ 200 µL of 3-aminopropyl triethoxysilane APTES is added, and the reaction is carried out at 70 °C under reflux or at room temperature with stirring for 6 ~ 8 hours, after the reaction, the unreacted APTES is removed by centrifugal washing, obtaining NH2-SiO2@CsPbBr3; 5 ~ 8 mg of NH2-SiO2@CsPbBr3 is dispersed in 1 ~ 2 mL of phosphate buffer PBS, 500 ~ 800 µL of the dispersion is mixed with 10 ~ 20 µL of glutaraldehyde and 500 ~ 800 µL of DNA2, and shaken, and incubated at 4 °C for 12 ~ 24 hours, after the incubation is completed, the product is washed and centrifuged with PBS, and after the washing is completed, it is redispersed in 1 mL of PBS and stored in a 4 °C refrigerator.

[0014] Preparation of electrochemiluminescence sensor 1) Polishing the bare glassy carbon electrode with Φ = 4 mm with 1.0, 0.3, 0.05 μm alumina slurry, then ultrasonic treatment in deionized water, rinsing with ethanol, and finally drying in a nitrogen atmosphere; 2) Ultrasonicating 4 ~ 8 mg / mL Nb:CuBi2O4@Au NPs dispersion to make all particles uniformly dispersed into a suspension, and dropping 10 μL of the Nb:CuBi2O4@Au NPs suspension on the surface of the glassy carbon electrode GCE, and storing at 4 ℃ until slightly moist, thus obtaining a GCE / Nb:CuBi2O4@Au NPs electrode; 3) Dropping 5 ~ 10 mL of 1.0 μM thiol-modified DNA1 5'−SH−C6−AAA AGA TTG CAC TTACTA TCT AAT TGA ATA−3' on the electrode surface, and incubating at room temperature for 1.5 hours, so that DNA1 is grown on the electrode through Au-S bonding with the gold nanoparticles on the electrode surface, and in the next step, 3 ~ 8 μL of bovine serum albumin BSA solution is modified on the electrode surface to block non-specific binding sites, and when the glassy carbon surface is about to dry, using PBS with pH 7.4 to rinse the excess BSA from the electrode surface; 4) Dropping 5 ~ 10 mL of SiO2@CsPbBr3-DNA2 on the electrode surface, and after incubating at room temperature for 1.5 hours, thoroughly rinsing the sample with PBS with pH 7.4 to remove excess bioconjugates, and modifying 5 ~ 10 mL of fumonisin B1 standard solution with different concentrations on the electrode surface, and reacting at 4 ℃ for 1 hour, so that SiO2@CsPbBr3-DNA2 completely recognizes and binds fumonisin B1, and finally, an electrochemiluminescence sensor for rapid detection of fumonisin B1 with signal enhancement is prepared.

[0015] 6. The electrochemiluminescence sensor prepared by the method of claim 5, wherein the detection method comprises the following steps: (1) Using an electrochemiluminescence instrument to test in a three-electrode system, with a silver / silver chloride electrode as the reference electrode, a platinum electrode as the auxiliary electrode, and the prepared sensor as the working electrode, and testing in 10 mL of PBS with pH 6.0 ~ 8.5 and containing 60 ~ 80 mM tripropylamine; (2) Detecting zearalenone by time-light intensity and cyclic voltammetry, setting the voltage to 0 ~ 1.6 V, the high voltage to 600 ~ 800 V, the amplification stage to 1 ~ 4, and the scanning rate to 0.1 ~ 0.8 V / s; (3) The sample solution to be detected containing fumonisin B1 is used instead of the fumonisin B1 standard solution for detection. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 Scanning electron microscope image of the Nb:CuBi2O4@Au NPs prepared for Example 1.

[0017] Figure 2 Transmission electron microscope image of the SiO2@CsPbBr3 prepared for Example 4.

[0018] Figure 3 Selectivity of the electrode material and electrochemiluminescence sensor for fumonisin B1 detection prepared according to Examples 1, 4, 7, 10, 13.

[0019] Figure 4 Stability of the electrode material and electrochemiluminescence sensor for fumonisin B1 detection prepared according to Examples 2, 5, 8, 11, 14.

[0020] Figure 5 Linear range chart of the electrode material and electrochemiluminescence sensor for fumonisin B1 detection prepared according to Examples 3, 6, 9, 12, 15.

[0021] (1) High signal intensity: Nb:CuBi2O4@Au NPs exert a synergistic effect of "catalytic enhancement" and "plasmonic enhancement", which amplifies the ECL signal by tens to hundreds of times compared with traditional systems.

[0022] (2) Excellent stability: The SiO2 shell effectively isolates water and oxygen from damaging the CsPbBr3 core, allowing it to maintain long-term ECL activity in aqueous buffer.

[0023] (3) Excellent sensitivity: Due to the significant enhancement of the signal, the detection limit of this sensor for fumonisin B1 can be as low as pg / mL, far superior to many existing methods.

[0024] (4) Good selectivity: Based on the high specificity of base pairing in DNA chains, this sensor can effectively exclude the interference of common coexisting substances such as other mycotoxins.

[0025] (5) Wide application prospect: This platform strategy is highly versatile, and by replacing the fixed biological recognition elements, it can be widely applied to the detection of various targets such as disease markers, heavy metal ions, and antibiotics. DETAILED DESCRIPTION

[0026] The application will be further described below with specific examples. EXAMPLES

[0027] Preparation of gold nanoparticles supported on niobium doped bismuth copper oxide, Nb:CuBi2O4@Au NPs (1) Preparation of Nb:CuBi2O4 Weigh 2.5 mg of copper nitrate pentahydrate Cu(NO3)2·5H2O, 9.7 mg of bismuth nitrate pentahydrate Bi(NO3)3·5H2O and 0.054 mg of niobium oxalate C 10 H5NbO 20 Dissolve in 5 mL of 2 M dilute nitric acid, magnetically stir until completely clear, under vigorous stirring, add 4 M sodium hydroxide solution drop by drop to the solution until the pH value of the solution reaches 10, in the process, it can be observed that the solution gradually turns dark and a large amount of precipitate is produced, Transfer the mixed suspension to a polytetrafluoroethylene lined autoclave, control the filling degree at 70% ~80%, seal the autoclave, put it into a blast drying oven, react at 160 °C for 12 hours, after the reaction is completed, naturally cool to room temperature, Open the autoclave, transfer the reaction product to a centrifuge tube, wash with deionized water and anhydrous ethanol alternately for at least 3 times each, until the supernatant is neutral, put the collected precipitate into a vacuum drying oven, dry at 60 °C for 6 hours, get dark brown Nb:CuBi2O4 powder, in order to obtain better crystallinity, the dried powder can be annealed in a muffle furnace, calcined at 400 °C for 2 hours; (2) Preparation of Nb:CuBi2O4@Au NPs Weigh 30 mg of Nb:CuBi2O4 powder, disperse in 100 mL of deionized water, ultrasonic treatment for 30 minutes, make it fully dispersed, form a uniform suspension, place the suspension in a round-bottom flask, heat to boiling under magnetic stirring, Quickly add 150 μL of 1 wt% chloroauric acid solution, keep boiling and stirring, quickly add 11.4 mg of trisodium citrate solution, continue refluxing for 30 minutes, it can be observed that the solution color gradually changes from the initial dark brown to purple black or gray black, which indicates that gold nanoparticles have been successfully generated and supported on the surface of Nb:CuBi2O4, stop heating, let the reaction system cool naturally to room temperature, centrifuge wash the reaction product with deionized water several times to remove unreacted reagents and free gold nanoparticles, dry the final product in a vacuum drying oven at 50 °C for 6 hours, to obtain the final Nb:CuBi2O4@Au NPs. Example

[0028] Preparation of gold nanoparticles supported on niobium doped bismuth copper oxide, Nb:CuBi2O4@Au NPs (1) Preparation of Nb:CuBi2O4 Take 7.5 mg of copper nitrate pentahydrate Cu(NO3)2·5H2O, 30 mg of bismuth nitrate pentahydrate Bi(NO3)3·5H2O and 0.1 mg of niobium oxalate C 10 H5NbO 20 Dissolve in 7.5 mL of 2 M dilute nitric acid, magnetically stir until completely clear, under vigorous stirring, add 4 M sodium hydroxide solution drop by drop to the solution until the pH value of the solution reaches 11, in the process, it can be observed that the solution gradually turns dark and a large amount of precipitate is produced, Transfer the mixed suspension to a polytetrafluoroethylene lined autoclave, control the filling degree at 70% ~80%, seal the autoclave, and put it into a forced air drying oven for reaction at 170 °C for 18 hours, after the reaction is completed, naturally cool to room temperature, Open the autoclave, transfer the reaction product to a centrifuge tube, and wash with deionized water and anhydrous ethanol alternately for at least 3 times each until the supernatant is neutral, put the collected precipitate into a vacuum drying oven and dry at 70 °C for 9 hours, get dark brown Nb:CuBi2O4 powder, in order to obtain better crystallinity, the dried powder can be annealed in a muffle furnace, calcined at 450 °C for 2 hours; (2) Preparation of Nb:CuBi2O4@Au NPs Take 50 mg of Nb:CuBi2O4 powder, disperse in 100 mL of deionized water, ultrasonic treatment for 30 minutes, make it fully dispersed, form a uniform suspension, place the suspension in a round-bottom flask, heat to boiling under magnetic stirring, Quickly add 225 μL of 1 wt% chloroauric acid solution, keep boiling and stirring, quickly add 18 mg of trisodium citrate solution, continue refluxing for 45 minutes, it can be observed that the solution color gradually changes from the initial dark brown to purple black or gray black, which indicates that gold nanoparticles have been successfully generated and loaded on the surface of Nb:CuBi2O4, stop heating, let the reaction system cool to room temperature naturally, wash the reaction product with deionized water several times by centrifugation to remove unreacted reagents and free gold nanoparticles, dry the final product in a vacuum drying oven at 55 °C for 9 hours, and the final Nb:CuBi2O4@Au NPs can be obtained. Example

[0029] Preparation of niobium-doped copper bismuthate loaded gold nanoparticles Nb:CuBi2O4@Au NPs (1) Preparation of Nb:CuBi2O4 Take 7.5 mg of copper nitrate pentahydrate Cu(NO3)2·5H2O, 30 mg of bismuth nitrate pentahydrate Bi(NO3)3·5H2O and 0.1 mg of niobium oxalate C10 H5NbO 20 , dissolved in 10 mL of 2 M dilute nitric acid, magnetic stirring until completely clear, under vigorous stirring, to the solution dropwise addition of 4 M sodium hydroxide solution until the pH value of the solution to 12, in the process, will be observed solution gradually changed to dark and a large amount of precipitate, The mixed suspension was transferred to a polytetrafluoroethylene lined autoclave, the filling degree was controlled at 70% ~80%, the autoclave was sealed, and it was placed in a blast drying oven at 180 °C for 24 hours. After the reaction was completed, it was naturally cooled to room temperature. The autoclave was opened, and the reaction product was transferred to a centrifuge tube. It was washed with deionized water and anhydrous ethanol alternately for at least 3 times each until the supernatant was neutral. The collected precipitate was placed in a vacuum drying oven and dried at 80 °C for 12 hours. A dark brown Nb:CuBi2O4 powder was obtained. In order to obtain better crystallinity, the dried powder can be annealed in a muffle furnace at 500 °C for 2 hours. (2) Preparation of Nb:CuBi2O4@Au NPs 70 mg of Nb:CuBi2O4 powder was weighed and dispersed in 100 mL of deionized water. It was ultrasonically treated for 30 minutes to make it fully dispersed to form a uniform suspension. The suspension was placed in a round-bottom flask and heated to boiling under magnetic stirring. 350 μL of 1 wt% chloroauric acid solution was quickly added. Boiling and stirring were maintained. 26.6 mg of trisodium citrate solution was quickly added. The reflux reaction was continued for 60 minutes. It was observed that the color of the solution gradually changed from the initial dark brown to purple black or gray black, which indicated that gold nanoparticles had been successfully generated and loaded on the surface of Nb:CuBi2O4. The heating was stopped, and the reaction system was naturally cooled to room temperature. The reaction product was centrifuged with deionized water several times to remove unreacted reagents and free gold nanoparticles. The final product was dried in a vacuum drying oven at 60 °C for 12 hours to obtain the final Nb:CuBi2O4@Au NPs. Example

[0030] Preparation of three-dimensional perovskite quantum dots and silica core-shell structure SiO2@CsPbBr3 (1) Preparation of three-dimensional perovskite quantum dots CsPbBr3 73.4 mg of lead bromide and 42.6 mg of cesium bromide were weighed and placed in a sample bottle. 5 mL of N, N-dimethylformamide was added. It was stirred vigorously to completely dissolve. 0.5 mL of oleic acid and 0.5 mL of oleylamine were added in turn. These ligands can coordinate with Pb 2+Coordination, control the crystal growth and passivation of surface defects, continue to stir until the solution is completely clear, to obtain CsPbBr3 precursor solution, this solution needs to be prepared on demand; (2) Preparation of reverse microemulsion and coating In a round-bottom flask equipped with a magnetic stirrer, 20 mL of cyclohexane, 5 mL of Triton X-100 and 5 mL of n-hexanol were added in sequence, and stirred vigorously at room temperature for 10 minutes to make them well mixed, obtaining an oil phase mixture; 100 μL of CsPbBr3 precursor solution was taken and added dropwise into the oil phase mixture, and the stirring was continued for 30 minutes. At this time, the system formed a clear and transparent reverse microemulsion, and the CsPbBr3 precursor was wrapped in the "water core" of the microemulsion; To the microemulsion, 200 μL of tetraethyl orthosilicate was added as a precursor for the silica SiO2 shell, and 100 μL of ammonia was added as a catalyst for the hydrolysis and condensation of tetraethyl orthosilicate. The reaction system was sealed and stirred slowly at room temperature for 12 hours; After the reaction was completed, an equal volume of acetone was added to the reaction solution to destroy the microemulsion system, and the product was precipitated. The mixture was transferred to a centrifuge tube and centrifuged at 8000-10000 rpm for 5-10 minutes. The precipitate was collected, and in order to completely remove the surfactant, unreacted reagents and by-products, the precipitate was washed with ethanol / acetone mixture at a volume ratio of 1:1 or alternatively with ethanol and acetone. Each washing required ultrasonic dispersion followed by centrifugation. The final light green precipitate was dried in a vacuum drying oven at 40-50 °C for 4-6 hours. The final product was a light green powder, which should be stored in a sealed container at 4 °C to prevent degradation. Example

[0031] The preparation of three-dimensional perovskite quantum dots and silica core-shell structure SiO2@CsPbBr3 is as follows: (1) Preparation of three-dimensional perovskite quantum dots CsPbBr3 100 mg of lead bromide and 60 mg of cesium bromide were weighed into a sample bottle, 7.5 mL of N, N-dimethylformamide was added, and the mixture was stirred vigorously to completely dissolve. 0.75 mL of oleic acid and 0.75 mL of oleylamine were added in sequence, which can coordinate with Pb 2+ Coordination, control the crystal growth and passivation of surface defects, continue to stir until the solution is completely clear, to obtain CsPbBr3 precursor solution, this solution needs to be prepared on demand; (2) Preparation of reverse microemulsion and coating In a round bottom flask equipped with a magnetic stirrer, 25 mL of cyclohexane, 7.5 mL of Triton X-100 and 7.5 mL of n-hexanol were sequentially added, and stirred vigorously at room temperature for 15 minutes to make them uniformly mixed to obtain an oil phase mixture; 150 μL of the CsPbBr3 precursor solution was taken and added dropwise into the oil phase mixture, and the stirring was continued for 30 minutes. At this time, the system formed a clear and transparent reverse microemulsion, and the CsPbBr3 precursor was wrapped in the "water core" of the microemulsion; To the microemulsion, 300 μL of tetraethyl orthosilicate as a precursor of the silica SiO2 shell and 150 μL of ammonia as a catalyst for the hydrolysis and condensation of tetraethyl orthosilicate were sequentially added, and the reaction system was sealed and continuously stirred slowly at room temperature for 18 hours; After the reaction was completed, an equal volume of acetone was added to the reaction solution to destroy the microemulsion system, and the product was precipitated. The mixture was transferred to a centrifuge tube and centrifuged at 8000-10000 rpm for 5-10 minutes. The precipitate was collected, and in order to completely remove the surfactant, unreacted reagents and by-products, the precipitate was washed with an ethanol / acetone mixture at a volume ratio of 1:1 or alternatively with ethanol and acetone. The final light green precipitate was dried in a vacuum drying oven at 40-50 °C for 4-6 hours. The final product was a light green powder, which should be stored in a sealed container at 4 °C in the dark to prevent degradation. Example

[0032] The preparation of three-dimensional perovskite quantum dots and silica core-shell structure SiO2@CsPbBr3 is as follows: (1) Preparation of three-dimensional perovskite quantum dots CsPbBr3 146.8 mg of lead bromide and 85.1 mg of cesium bromide were weighed into a sample bottle, 10 mL of N, N-dimethylformamide was added, and the mixture was stirred vigorously until it was completely dissolved. 1.0 mL of oleic acid and 1.0 mL of oleylamine were sequentially added to the mixture. These ligands can coordinate with Pb 2+ to control the crystal growth and passivate surface defects. The stirring was continued until the solution was completely clear to obtain a CsPbBr3 precursor solution. This solution should be prepared immediately before use; (2) Preparation of reverse microemulsion and coating In a round bottom flask equipped with a magnetic stirrer, 30 mL of cyclohexane, 10 mL of Triton X-100 and 10 mL of n-hexanol were sequentially added, and stirred vigorously at room temperature for 20 minutes to make them uniformly mixed to obtain an oil phase mixture; Take 200 μΐ of CsPbBr3 precursor solution and add it dropwise into the oil phase mixture, continue to stir vigorously for 30 minutes, at this time the system will form a clear and transparent inverse microemulsion, and the CsPbBr3 precursor will be wrapped in the "water core" of the microemulsion; Add the following into the microemulsion in sequence: 400 μΐ of tetraethyl orthosilicate as the precursor of the silica SiO2 shell, 200 μΐ of ammonia as the catalyst for the hydrolysis and condensation of tetraethyl orthosilicate, seal the reaction system, and continue to stir slowly at room temperature for 24 hours. After the reaction is completed, add an equal volume of acetone to the reaction solution to destroy the microemulsion system, and make the product precipitate. Transfer the mixture to a centrifuge tube, centrifuge at 8000-10000 rpm for 5-10 minutes, collect the precipitate at the bottom, and in order to completely remove the surfactant, unreacted reagents and by-products, the precipitate needs to be washed with an ethanol / acetone mixture in a volume ratio of 1:1 or alternatively with ethanol and acetone, and the washing needs to be repeated multiple times, each time followed by ultrasonic dispersion and centrifugation. Dry the final light green precipitate in a vacuum drying oven at 40-50 °C for 4-6 hours. The final product is a light green powder, which should be stored in a sealed container in the dark at 4 °C in the refrigerator to prevent degradation. Example

[0033] Preparation of three-dimensional perovskite quantum dots and silica core-shell structure-DNA2 hybrid SiO2@CsPbBr3-DNA2 (1) Preparation of amino-functionalized three-dimensional perovskite quantum dots and silica core-shell structure NH2-SiO2@CsPbBr3 Disperse 200 mg of SiO2@CsPbBr3 nanoparticles in anhydrous toluene or ethanol, add 100 μΐ of 3-aminopropyltriethoxysilane APTES, and heat under reflux at 70 °C or stir at room temperature for 6 hours. After the reaction, remove the unreacted APTES by centrifugal washing to obtain NH2-SiO2@CsPbBr3. (2) Preparation of three-dimensional perovskite quantum dots and silica core-shell structure-DNA2 hybrid SiO2@CsPbBr3-DNA2 Disperse 5 mg of NH2-SiO2@CsPbBr3 in 1 mL of phosphate buffer PBS, take 500 μΐ of the dispersion and mix it with 10 μΐ of glutaraldehyde and 500 μΐ of DNA2, shake, and incubate at 4 °C for 12 hours. After the incubation is completed, wash and centrifuge with PBS, and after the washing is completed, re-disperse in 1 mL of PBS and store in a 4 °C refrigerator for later use. Example

[0034] (1) Preparation of aminated three-dimensional perovskite quantum dots and silica core-shell structure NH2-SiO2@CsPbBr3 Disperse 300 mg of SiO2@CsPbBr3 nanoparticles in anhydrous toluene or ethanol, add 150 µL of 3-aminopropyl triethoxysilane APTES, heat under reflux at 70 °C or stir at room temperature for 7 hours, after the reaction, remove the unreacted APTES by centrifugal washing to obtain NH2-SiO2@CsPbBr3; (2) Preparation of three-dimensional perovskite quantum dots and silica core-shell structure-DNA2 hybrid SiO2@CsPbBr3-DNA2 Disperse 6.5 mg of NH2-SiO2@CsPbBr3 in 1.5 mL of phosphate buffer PBS, take 650 µL of the dispersion and mix with 15 µL of glutaraldehyde and 650 µL of DNA2, shake, incubate at 4 °C for 18 hours, after incubation, wash by centrifugal washing with PBS, after washing, redispersed in 1 mL of PBS, placed in a 4 °C refrigerator for standby. Example

[0035] (1) Preparation of aminated three-dimensional perovskite quantum dots and silica core-shell structure NH2-SiO2@CsPbBr3 Disperse 400 mg of SiO2@CsPbBr3 nanoparticles in anhydrous toluene or ethanol, add 200 µL of 3-aminopropyl triethoxysilane APTES, heat under reflux at 70 °C or stir at room temperature for 8 hours, after the reaction, remove the unreacted APTES by centrifugal washing to obtain NH2-SiO2@CsPbBr3; (2) Preparation of three-dimensional perovskite quantum dots and silica core-shell structure-DNA2 hybrid SiO2@CsPbBr3-DNA2 Disperse 8 mg of NH2-SiO2@CsPbBr3 in 2 mL of phosphate buffer PBS, take 800 µL of the dispersion and mix with 20 µL of glutaraldehyde and 800 µL of DNA2, shake, incubate at 4 °C for 24 hours, after incubation, wash by centrifugal washing with PBS, after washing, redispersed in 1 mL of PBS, placed in a 4 °C refrigerator for standby. Example

[0036] Preparation of an electrochemiluminescence sensor 1) Polish the bare glassy carbon electrode with Φ = 4 mm with 1.0 μm alumina slurry, then ultrasonic treatment in deionized water, rinse with ethanol, and finally dry in a nitrogen atmosphere; 2) 4 mg / mL Nb:CuBi2O4@Au NPs dispersion liquid was ultrasonicated until all particles were uniformly dispersed into a suspension, 10 μL of Nb:CuBi2O4@Au NPs suspension was drop-coated on the surface of the glassy carbon electrode GCE, and the GCE / Nb:CuBi2O4@Au NPs electrode was obtained by storing at 4 °C until slightly wet; 3) 5 mL of 1.0 μM thiol-modified DNA1 5'-SH-C6-AAA AGA TTG CAC TTA CTA TCTAAT TGA ATA-3' was added dropwise on the electrode surface, and incubated at room temperature for 1.5 hours. DNA1 was immobilized on the electrode through Au-S bond with gold nanoparticles on the electrode surface. In the next step, 3 μL of bovine serum albumin BSA solution was modified on the electrode surface to block non-specific binding sites. When the glassy carbon surface was about to dry, the excess BSA was washed off from the electrode surface using PBS with pH 7.4; 4) 5 mL of SiO2@CsPbBr3-DNA2 was added dropwise on the electrode surface, and incubated at room temperature for 1.5 hours. Then, the sample was thoroughly washed with PBS with pH 7.4 to remove excess bioconjugates. 5 mL of fumonisin B1 standard solution with different concentrations was modified on the electrode surface, and reacted at 4 °C for 1 hour to allow SiO2@CsPbBr3-DNA2 to completely recognize and bind fumonisin B1. Finally, a signal-enhanced rapid detection of fumonisin B1 electrochemiluminescence sensor was prepared. Embodiment

[0037] Preparation of electrochemiluminescence sensor 1) A bare glassy carbon electrode with Φ = 4 mm was polished with 0.3 μm alumina slurry, and then ultrasonicated in deionized water. The electrode was rinsed with ethanol and finally dried in a nitrogen atmosphere; 2) 6 mg / mL Nb:CuBi2O4@Au NPs dispersion liquid was ultrasonicated until all particles were uniformly dispersed into a suspension, 10 μL of Nb:CuBi2O4@Au NPs suspension was drop-coated on the surface of the glassy carbon electrode GCE, and the GCE / Nb:CuBi2O4@Au NPs electrode was obtained by storing at 4 °C until slightly wet; 3) 7.5 mL of 1.0 μM thiol-modified DNA1 5'-SH-C6-AAA AGA TTG CAC TTA CTA TCT AAT TGA ATA-3' was added to the electrode surface and incubated at room temperature for 1.5 hours, and DNA1 was grown on the electrode through Au-S with the gold nanoparticles on the electrode surface. Next, 5.5 μL of a bovine serum albumin (BSA) solution was modified on the electrode surface to block non-specific binding sites. When the glassy carbon surface was about to dry, the excess BSA was washed off the electrode surface using PBS with a pH of 7.4; 4) 7.5 mL of SiO2@CsPbBr3-DNA2 was added to the electrode surface and incubated at room temperature for 1.5 hours. The sample was then thoroughly washed with PBS with a pH of 7.4 to remove excess biological conjugates. 7.5 mL of a fumonisin B1 standard solution with different concentrations was modified on the electrode surface and reacted at 4°C for 1 hour, so that SiO2@CsPbBr3-DNA2 could completely recognize and bind fumonisin B1. Finally, an electrochemiluminescence sensor for rapid detection of fumonisin B1 with signal enhancement was prepared. Embodiment

[0038] Preparation of an electrochemiluminescence sensor 1) A bare glassy carbon electrode with a diameter of Φ = 4 mm was polished with a 0.05 μm alumina slurry, then ultrasonically treated in deionized water, rinsed with ethanol, and finally dried in a nitrogen atmosphere; 2) 8 mg / mL of Nb:CuBi2O4@Au NPs dispersion was ultrasonically treated until all the particles were uniformly dispersed as a suspension. 10 μL of the Nb:CuBi2O4@Au NPs suspension was drop-coated on the glassy carbon electrode (GCE) surface, and the GCE / Nb:CuBi2O4@Au NPs electrode was stored at 4°C until it was slightly moist; 3) 10 mL of 1.0 μM thiol-modified DNA1 5'-SH-C6-AAA AGA TTG CAC TTA CTA TCT AAT TGA ATA-3' was added to the electrode surface and incubated at room temperature for 1.5 hours, and DNA1 was grown on the electrode through Au-S with the gold nanoparticles on the electrode surface. Next, 8 μL of a bovine serum albumin (BSA) solution was modified on the electrode surface to block non-specific binding sites. When the glassy carbon surface was about to dry, the excess BSA was washed off the electrode surface using PBS with a pH of 7.4; 4) 10 mL SiO2@CsPbBr3-DNA2 was added dropwise on the electrode surface, after incubation at room temperature for 1.5 hours, the sample was thoroughly rinsed with PBS with pH of 7.4 to remove the excess bioconjugate, 10 mL of fumonisin B1 standard solution with different concentrations was modified on the electrode surface, and reacted at 4 ℃ for 1 hour, so that SiO2@CsPbBr3-DNA2 could completely recognize and bind fumonisin B1, finally, an electrochemiluminescence sensor for rapid detection of fumonisin B1 with signal enhancement was prepared. Embodiment

[0039] Application of an electrochemiluminescence sensing method for rapid detection of fumonisin B1 with signal enhancement (1) The electrochemiluminescence instrument was used to test in a three-electrode system, the silver / silver chloride electrode was the reference electrode, the platinum electrode was the auxiliary electrode, and the prepared sensor was the working electrode, and the test was carried out in 10 mL of PBS with pH of 6.0 and containing 60 mM tripropylamine; (2) The time-light intensity and cyclic voltammetry were used to detect zearalenone, the voltage was set to 0 ~ 1.6 V, the high voltage was set to 600 V, the amplification level was 1, and the scanning rate was 0.1 V / s; (3) The sample solution containing fumonisin B1 to be detected was used instead of the fumonisin B1 standard solution for detection. Embodiment

[0040] Application of an electrochemiluminescence sensing method for rapid detection of fumonisin B1 with signal enhancement (1) The electrochemiluminescence instrument was used to test in a three-electrode system, the silver / silver chloride electrode was the reference electrode, the platinum electrode was the auxiliary electrode, and the prepared sensor was the working electrode, and the test was carried out in 10 mL of PBS with pH of 7.4 and containing 70 mM tripropylamine; (2) The time-light intensity and cyclic voltammetry were used to detect zearalenone, the voltage was set to 0 ~ 1.6 V, the high voltage was set to 700 V, the amplification level was 3, and the scanning rate was 0.5 V / s; (3) The sample solution containing fumonisin B1 to be detected was used instead of the fumonisin B1 standard solution for detection. Embodiment

[0041] Application of an electrochemiluminescence sensing method for rapid detection of fumonisin B1 with signal enhancement (1) The electrochemiluminescence instrument was used to test in a three-electrode system, the silver / silver chloride electrode was the reference electrode, the platinum electrode was the auxiliary electrode, and the prepared sensor was the working electrode, and the test was carried out in 10 mL of PBS with pH of 8.5 and containing 80 mM tripropylamine; (2) Detecting zearalenone by time-optical intensity and cyclic voltammetry, setting voltage as 0~1.6 V, setting high voltage as 800 V, amplification stage as 4, and scanning rate as 0.8 V / s; (3) Replacing the fumonisin B1 standard solution with the sample solution containing fumonisin B1 to be detected.

Claims

1. A material for rapid detection of fumonisin B1 with signal enhancement, characterized in that: Includes the following steps: (1) Preparation of niobium-doped copper bismuthate-supported gold nanoparticles Nb:CuBi2O4@Au NPs Using copper nitrate pentahydrate Cu(NO3)2·5H2O, bismuth nitrate pentahydrate Bi(NO3)3·5H2O, and niobium oxalate C 10 H5NbO 20 Reagents such as sodium hydroxide (NaOH) and nitric acid (HNO3) are used to crystallize Nb-doped CuBi2O4 crystals under high temperature and high pressure through hydrothermal reaction. Using chloroauric acid as the gold source, gold nanoparticles are nucleated and grown on the surface of Nb:CuBi2O4 under the action of reducing agents such as sodium citrate, thus obtaining Nb:CuBi2O4@Au NPs. (2) Preparation of three-dimensional perovskite quantum dots and silicon dioxide core-shell structure SiO2@CsPbBr3 Three-dimensional perovskite quantum dots were synthesized using reagents such as lead bromide, cesium bromide, N,N-dimethylformamide, oleic acid, and oleylamine. Cyclohexane was used as the oil phase, and surfactants formed micelles in the oil phase. The aqueous phase, including the precursor solution, was encapsulated in the micelles, forming tiny "reactors," i.e., reverse microemulsions. The nucleation and growth of perovskite, as well as the subsequent hydrolysis and condensation of tetraethyl orthosilicate to form a SiO2 shell, were all confined within these nanoscale reactors, thus obtaining a uniform and fully encapsulated core-shell structure, i.e., SiO2@CsPbBr3. (3) Preparation of three-dimensional perovskite quantum dots and silica core-shell structure-DNA2 hybrid SiO2@CsPbBr3-DNA2 SiO2@CsPbBr3 was aminated using 3-aminopropyltriethoxysilane to obtain NH2-SiO2@CsPbBr3. Then, NH2-SiO2@CsPbBr3 was combined with DNA2 containing an amino group using glutaraldehyde to obtain SiO2@CsPbBr3-DNA2.

2. The method for preparing a material for signal-enhanced rapid detection of fumonisin B1 according to claim 1, characterized in that, The preparation of niobium-doped copper bismuthate-supported gold nanoparticles (Nb:CuBi2O4@Au NPs) is as follows: (1) Preparation of niobium-doped copper bismuthate Nb:CuBi2O4 Weigh out 2.5 ~ 12.5 mg of copper nitrate pentahydrate Cu(NO3)2·5H2O, 9.7 ~ 48.5 mg of bismuth nitrate pentahydrate Bi(NO3)3·5H2O, and 0.054 ~ 0.27 mg of niobium oxalate C. 10 H5NbO 20 Dissolve the solution in 5-10 mL of 2 M dilute nitric acid and stir magnetically until completely clear. While stirring vigorously, add 4 M sodium hydroxide solution dropwise until the pH reaches 10-12. During this process, the solution will gradually turn darker and produce a large amount of precipitate. The mixed suspension was transferred to a polytetrafluoroethylene-lined high-pressure reactor, with the filling degree controlled at 70% to 80%. The reactor was sealed and placed in a forced-air drying oven, where it was reacted at 160 to 180 °C for 12 to 24 hours. After the reaction was completed, it was allowed to cool naturally to room temperature. Open the reaction vessel and transfer the reaction product to a centrifuge tube. Wash the product with deionized water and anhydrous ethanol at least three times each, alternating between centrifugation and washing, until the supernatant is neutral. Place the collected precipitate in a vacuum drying oven and dry it at 60-80 °C for 6-12 hours to obtain dark brown Nb:CuBi2O4 powder. To obtain better crystallinity, the dried powder can be annealed in a muffle furnace and calcined at 400-500 °C for 2 hours to obtain Nb:CuBi2O4. (2) Preparation of Nb:CuBi2O4@Au NPs Weigh 30-70 mg of Nb:CuBi2O4 powder, disperse it in 100 mL of deionized water, and sonicate it for 30 minutes to ensure thorough dispersion and form a homogeneous suspension. Place the suspension in a round-bottom flask and heat it to boiling under magnetic stirring. Quickly add 150-350 μL of 1 wt% chloroauric acid solution, maintain boiling and stirring, and rapidly add 11.4-26.6 mg of trisodium citrate solution. Continue reflux for 30-60 minutes. The solution color can be observed to gradually change from the initial dark brown to purplish-black or grayish-black, indicating that gold nanoparticles have been successfully generated and loaded onto the Nb:CuBi2O4 surface. Stop heating and allow the reaction system to cool naturally to room temperature. Centrifuge and wash the reaction product several times with deionized water to remove unreacted reagents and free gold nanoparticles. Dry the final product in a vacuum drying oven at 50-60 °C for 6-12 hours to obtain the final Nb:CuBi2O4@Au NPs.

3. The method for preparing a material for signal-enhanced rapid detection of fumonisin B1 according to claim 1, characterized in that, The preparation of three-dimensional perovskite quantum dots and silica core-shell structure SiO2@CsPbBr3 specifically involves: (1) Preparation of three-dimensional perovskite quantum dots CsPbBr3 Weigh 73.4–146.8 mg of lead bromide and 42.6–85.1 mg of cesium bromide, place them in a sample vial, add 5–10 mL of N,N-dimethylformamide, and stir vigorously until completely dissolved. Then, add 0.5–1.0 mL of oleic acid and 0.5–1.0 mL of oleylamine sequentially. These ligands can react with Pb. 2+ Coordination is performed to control crystal growth and passivate surface defects. The solution is stirred continuously until it is completely clear to obtain a CsPbBr3 precursor solution. This solution must be prepared fresh before use. (2) Preparation of reverse microemulsion and coating In a round-bottom flask equipped with a magnetic stirrer, add 20-30 mL of cyclohexane, 5-10 mL of Triton X-100 and 5-10 mL of n-hexanol in sequence, and stir vigorously at room temperature for 10-20 minutes to mix them evenly to obtain an oil phase mixture; Take 100 ~ 200 µL of CsPbBr3 precursor solution and add it dropwise to the oil phase mixture. Continue stirring vigorously for 30 minutes. At this time, a clear and transparent reverse microemulsion will be formed in the system, and the CsPbBr3 precursor will be encapsulated in the "water core" of the microemulsion. Add the following to the microemulsion in sequence: 200 ~ 400 µL of tetraethyl orthosilicate as a precursor for the silica (SiO2) shell, and 100 ~ 200 µL of ammonia as a catalyst for the hydrolysis and condensation of tetraethyl orthosilicate. Seal the reaction system and stir slowly at room temperature for 12-24 hours. After the reaction is complete, add an equal volume of acetone to the reaction solution to disrupt the microemulsion system and cause the product to precipitate. Transfer the mixture to a centrifuge tube and centrifuge at 8000-10000 rpm for 5-10 minutes. Collect the precipitate at the bottom. To thoroughly remove surfactants, unreacted reagents, and byproducts, the precipitate needs to be washed multiple times by centrifugation with an ethanol / acetone mixture at a 1:1 volume ratio or by alternating between ethanol and acetone. Each wash should be followed by ultrasonic dispersion and centrifugation. The resulting light green precipitate should be dried in a vacuum drying oven at 40-50 °C for 4-6 hours. The final product is a light green powder and should be sealed and stored in a refrigerator at 4 °C in a light-proof container to prevent degradation.

4. The method for preparing a material for signal-enhanced rapid detection of fumonisin B1 according to claim 1, characterized in that, The preparation of three-dimensional perovskite quantum dots and silica core-shell structure-DNA2 hybrid SiO2@CsPbBr3-DNA2 is as follows: (1) Preparation of aminated three-dimensional perovskite quantum dots and silica core-shell structure NH2-SiO2@CsPbBr3 200-400 mg of SiO2@CsPbBr3 nanoparticles were dispersed in anhydrous toluene or ethanol, and 100-200 µL of 3-aminopropyltriethoxysilane (APTES) was added. The mixture was heated under reflux at 70 °C or stirred at room temperature for 6-8 hours. After the reaction, unreacted APTES was removed by centrifugation and washing to obtain NH2-SiO2@CsPbBr3. (2) Preparation of three-dimensional perovskite quantum dots and silica core-shell structure-DNA2 hybrid SiO2@CsPbBr3-DNA2 Disperse 5-8 mg of NH2-SiO2@CsPbBr3 in 1-2 mL of phosphate-buffered saline (PBS). Take 500-800 µL of the dispersion, mix it with 10-20 µL of glutaraldehyde and 500-800 µL of DNA2, and vortex. Incubate at 4 °C for 12-24 hours. After incubation, wash with PBS and centrifuge. After washing, redisperse in 1 mL of PBS and store at 4 °C for later use.

5. A method for preparing an electrochemiluminescence sensor, comprising using the material prepared by the method described in claims 1-4, characterized in that, The fabrication method of the electrochemiluminescence sensor is as follows: 1) Polish the bare glassy carbon electrode with Φ = 4 mm using alumina slurry of 1.0, 0.3, and 0.05 μm, then sonicate it in deionized water, rinse it with ethanol, and finally dry it in a nitrogen atmosphere. 2) Sonicate the 4 ~ 8 mg / mL Nb:CuBi2O4@Au NPs dispersion until all particles are uniformly dispersed into a suspension. Drop 10µL of the Nb:CuBi2O4@Au NPs suspension onto the surface of the glassy carbon electrode GCE and store at 4 ℃ until slightly moist to obtain the GCE / Nb:CuBi2O4@Au NPs electrode. 3) Add 5-10 mL of 1.0 μM thiol-modified DNA1 5'−SH−C6−AAA AGA TTG CAC TTA CTATCT AAT TGA ATA−3' to the electrode surface and incubate at room temperature for 1.5 hours. DNA1 grows on the electrode through Au-S binding with gold nanoparticles on the electrode surface. Next, modify the electrode surface with 3-8 μL of bovine serum albumin (BSA) solution to block non-specific binding sites. When the glassy carbon surface is about to dry, wash away excess BSA from the electrode surface with PBS at pH 7.

4. 4) Add 5-10 mL of SiO2@CsPbBr3-DNA2 to the electrode surface and incubate at room temperature for 1.5 hours. Then, thoroughly wash the sample with PBS at pH 7.4 to remove excess bioconjugated material. Modify the electrode surface with 5-10 mL of fumonisin B1 standard solution of different concentrations and react at 4 °C for 1 hour to allow SiO2@CsPbBr3-DNA2 to fully recognize and bind to fumonisin B1. Finally, a signal-enhanced electrochemiluminescence sensor for rapid detection of fumonisin B1 is obtained.

6. A detection method for a signal-enhanced rapid detection electrochemiluminescence sensor of fumonisin B1, characterized in that, The steps are as follows: (1) The test was performed using an electrochemiluminescence analyzer with a three-electrode system. The silver / silver chloride electrode was used as the reference electrode, the platinum electrode was used as the auxiliary electrode, and the prepared sensor was used as the working electrode. The test was performed in 10 mL of PBS phosphate buffer solution containing 60-80 mM tripropylamine at pH 6.0-8.

5. (2) Time-intensity and cyclic voltammetry were used to detect zearalenone in zearalenone. The voltage was set to 0 ~ 1.6 V, the high voltage to 600 ~ 800 V, the amplification stage to 1 ~ 4, and the scan rate to 0.1 ~ 0.8 V / s. (3) The sample solution containing fumonisin B1 to be tested is used instead of the standard solution of fumonisin B1 for detection.

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