CN113203788B - Bimodal rapid detection method for acetamiprid in fruits and vegetables - Google Patents

Abstract

The invention belongs to the technical field of food detection, and relates to a bimodal rapid detection method for acetamiprid in fruits and vegetables; the bimodal nanoprobe with both fluorescence characteristic and electrochemical characteristic is constructed by combining the fluorescence technology and the electrochemical technology by utilizing the dual-signal characteristic of the zirconium-based metal organic framework for the first time, so that the bimodal detection of the single nanomaterial on the acetamiprid is realized. The bimodal detection of acetamiprid provided by the invention can reduce or eliminate low detection accuracy or false positive results caused by external factors such as substrate concentration, external environment, instrument conditions and the like. The correlation coefficients of the electrochemical and fluorescence method correlation prediction models respectively reach 0.998 and 0.997, and the selectivity and accuracy of the nano probe in a complex system are greatly improved.

Description

A dual-mode rapid detection method for acetamiprid in fruits and vegetables

technical field

The invention belongs to the technical field of food detection, and in particular relates to a method for rapidly detecting acetamiprid in fruits and vegetables in an electrochemical/fluorescence dual mode.

Background technique

my country is the world's largest producer of fruits and vegetables. In order to reduce the impact of diseases, insects, weeds and other harmful organisms on fruit and vegetable production, various functional pesticides are widely used in the process of fruit and vegetable planting. However, excessive pesticides applied during agricultural production will directly or indirectly remain on the surface of fruits and vegetables, seriously affecting the eating quality of fruits and vegetables and the health of consumers. Acetamiprid is a new broad-spectrum insecticide with acaricidal activity, which is widely used to control aphids, planthoppers and other pests in the process of fruit and vegetable cultivation. At present, the detection methods of acetamiprid with strong specificity and high sensitivity are all instrumental analysis methods with high detection cost, long cycle and complicated operation. In view of the influence of acetamiprid on the edibility of fruits and vegetables and the insufficiency of existing detection methods, it is of great practical significance to develop a rapid, convenient and accurate method for the detection of acetamiprid in fruits and vegetables.

The detection method of acetamiprid based on fluorescence technology and electrochemical technology has attracted much attention because of its high detection accuracy, fast speed and low cost. However, single fluorescence technology and electrochemical technology have their own advantages and disadvantages. In order to avoid the problem of false positive or false negative detection results, the dual-modal detection strategy combining fluorescence technology and electrochemical technology has become the current rapid detection method. important research directions in the field. Combining fluorescence technology and electrochemical technology to construct dual-mode nanoprobes with both fluorescence and electrochemical properties can overcome the limitations of a single technology, self-correct the detection results in a targeted manner, and improve the accuracy of the detection results , play a complementary role. The existing methods for detecting acetamiprid based on dual-modal nanoprobes have the following two deficiencies. One is that the nanoprobes constructed for the dual-modal detection use complex nanomaterials, and the synthesis process is cumbersome; the other is the need for A variety of nanomaterials interact to realize the dual-mode detection of fluorescence and electrochemistry. The interaction between various nanomaterials leads to poor stability of the probe.

Contents of the invention

In order to make up for the deficiencies of the prior art, the present invention provides a rapid detection method for acetamiprid in fruits and vegetables based on zirconium-based metal organic frameworks, which can realize the electrochemical/fluorescence dual-mode rapid and low-cost detection of acetamiprid in fruits and vegetables . The zirconium-based metal-organic framework in the invention has both fluorescence characteristics and electrochemical characteristics, and the synthesis is simple and the cost is low.

For realizing the foregoing invention object, concrete technical scheme of the present invention is as follows:

A method for rapid detection of acetamiprid dual modes in fruits and vegetables, comprising the following steps:

(1) Preparation of zirconium-based metal-organic frameworks

S1. Dissolve zirconium tetrachloride and 2-aminoterephthalic acid in N,N-dimethylformamide, mix them with ultrasonic vibration, add glacial acetic acid, continue to stir to obtain a mixed solution, transfer it to a reaction kettle, and The reaction is carried out under a certain temperature condition, and after the reaction, the product is washed several times with N,N-dimethylformamide and methanol successively, and dried in a vacuum drying oven to obtain a purified zirconium-based metal-organic framework;

S2. Acetamiprid aptamer modification of zirconium-based metal-organic frameworks: acetamiprid aptamer solution and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC ) and N-hydroxysuccinimide (NHS), stirring and incubating at room temperature, adding the zirconium-based metal-organic framework purified in step S1, incubating at room temperature, and then centrifuging the product, the obtained solid precipitate is acetidine Zirconium-based metal-organic frameworks modified by amidine aptamers;

(2) Acquisition of electrochemical and fluorescent signals

S1. Electrode pretreatment: Polish the gold electrode with alumina powder of different particle sizes on the polishing flannelette, then ultrasonically treat it in absolute ethanol and deionized water, and dry it with nitrogen; then place it in sulfuric acid solution for cyclic potential Scan and observe its oxidation and reduction peak potentials until the oxidation and reduction peaks completely overlap to obtain an activated gold electrode;

S2. Gold electrode acetamiprid aptamer complementary chain modification: Add the acetamiprid aptamer complementary chain solution dropwise on the surface of the activated gold electrode described in S1 of step (2), and rinse with deionized water after incubation at room temperature Rinse the unbound acetamiprid aptamer complementary chain solution on the surface; then add bovine serum albumin solution (BSA) dropwise, and rinse the electrode surface with deionized water after standing at room temperature for a period of time to obtain the acetamiprid aptamer complementary chain Modified gold electrodes;

S3. Determination by pulse voltammetry: Prepare standard samples of acetamiprid with different concentrations, which are respectively recorded as C ₁ , C ₂ ,...,C _n-1 , C _n , where n is a positive integer; Add the zirconium-based metal-organic framework modified by the acetamiprid aptamer obtained in S2 of step (1) to obtain a mixed solution; the acetamiprid aptamer complementary chain modified gold obtained in S2 of step (2) The electrode is inserted into the above mixed solution, stirred and enriched for a period of time, so that the zirconium-based metal-organic framework modified by the acetamiprid aptamer is connected to the gold electrode modified by the complementary chain of the acetamiprid aptamer through complementary base pairing; After completion, stop stirring and let the solution stand for a period of time. During this process, the zirconium-based metal-organic framework modified by the acetamiprid aptamer is attached to the surface of the gold electrode modified by the complementary chain of the acetamiprid aptamer, and the working electrode is obtained;

S4. Electric signal acquisition stage: carry out potential scanning to the working electrode described in S3 of step (2), the potential scans from 1.2V to 0.5V, obtains the electrical signal of the working electrode, uses the working electrode to measure and record different concentrations of acetidine The electrical signal intensity of amidine standard samples (C ₁ , C ₂ ,...,C _n-1 ,C _n ), denoted as E ₁ ,E ₂ ,...,E _n-1 ,E _n , where n is a positive integer;

S5. Fluorescence signal acquisition stage: After measuring the electrical signal intensity of acetamiprid standard sample of a concentration, take out the working electrode and rinse the surface of the working electrode with phosphate buffer, and collect and wash the phosphate buffer of this concentration. Acetamiprid standard samples are mixed; after this operation, a mixture of different concentrations of acetamiprid standard samples and the washed phosphate buffer solution will be obtained. Put it into a quartz cuvette, set the excitation wavelength of the fluorescence spectrometer, measure and record its optimal fluorescence emission intensity, and record it as F ₁ , F,...,F _n-1 ,F _n , where n is a positive integer; (3 ) rapid prediction of acetamiprid concentration

S1. Electrochemical rapid detection prediction model: According to the electrical signal strength E ₁ , E ₂ , ... , E _n-1 , E n described in S4 of step (2), E _n is compared with different concentrations of acetamiprid standard sample C ₁ , C ₂ ,..., C _n-1 , C _n build a model to obtain the electrochemical rapid detection prediction model E=f(X) of acetamiprid, where E is the electrochemical current, and X is the concentration of acetamiprid , n is a positive integer;

S2. Fluorescence rapid detection prediction model: compare the fluorescence emission intensities F ₁ , F, ... , F _n-1 , F _n described in S5 of step (2) with different concentrations of acetamiprid standard samples C ₁ , C ₂ ,...,C _n-1 ,C _n establishes a model, and obtains acetamiprid's fluorescence rapid detection prediction model F=f(X), wherein F is the fluorescence emission intensity, X is the concentration of acetamiprid, and n is a positive integer ;

S3. Rapid prediction of the concentration of acetamiprid in fruits and vegetables: Take the fruit and vegetable samples to be tested and cut them into pieces or grind them into pieces, then add the general extract of the samples, fully oscillate and mix, and then it is the solution to be tested; follow steps (2) in S4 and S5 The method of measuring the electrochemical signal and the fluorescence signal obtains the electric signal intensity and the fluorescence emission intensity respectively, and brings them into the electrochemical rapid detection prediction model and the fluorescence rapid detection prediction model respectively, and obtains the acetamiprid obtained by the electrochemical method and the fluorescence method. Quickly predict the concentration value; the fast predicted concentration value of acetamiprid obtained by the electrochemical method and the fluorescence method is used to analyze the difference between groups using SPSS; if there is a significant difference between the two groups of data (p<0.05), the data will be discarded; If there is no significant difference between the two groups of data (p>0.05), the average value of the above data is taken as the concentration of acetamiprid in fruits and vegetables, so as to realize the rapid detection of the concentration of acetamiprid.

Preferably, the mol ratio of zirconium tetrachloride and 2-aminoterephthalic acid described in S1 of step (1) is 1:1; Described zirconium tetrachloride and 2-aminoterephthalic acid are in mixed solution The concentration is 8mmol·L- ¹ ; the volume ratio of the N,N-dimethylformamide and glacial acetic acid is 4:1; the time for the ultrasonic vibration mixing is 5 to 10 minutes; The temperature of the middle reaction is 110-150° C., and the time is 8-15 hours; the number of cleaning times is 1-4 times.

Preferably, the acetamiprid aptamer solution, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC), N-hydroxy The dosage ratio of succinimide (NHS) and purified zirconium-based metal-organic framework is 1mL:5mL:5mL: 1-2g; the concentration of the acetamiprid aptamer solution is 100 μmol/L; the 1-(3 The concentration of -dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride is 0.1mmol/L; the concentration of the N-hydroxysuccinimide is 0.1mmol/L; the acetamiprid is suitable The base sequence of the ligand is: 5'-(COOH)-(CH2)6-ACA GGC TAC GAG GGA AAT GCG GTGGGT GTG GGC GAT-3'.

Preferably, the time for stirring and incubating in S2 of step (1) is 1-2 hours; the time for incubating after adding the purified zirconium-based metal-organic framework is 10-12 hours.

Preferably, the particle sizes of the alumina powders with different particle sizes in S1 of step (2) are 1.0 μm, 0.3 μm, and 0.05 μm in sequence, and the grinding time is 3 to 5 minutes; the ultrasonic treatment time is 3 to 5 minutes ; The concentration of the sulfuric acid solution is 0.5mol/L.

Preferably, the base sequence of the acetamiprid aptamer complementary strand described in S2 of step (2) is: 5'-(SH)-(CH2)6-TGT CCG ATG CTC-3'; the acetamiprid The concentration of the amidine aptamer complementary strand solution is 100 μmol/L, and the amount dropped on the surface of the activated gold electrode is 5-10 μL; the incubation time at normal temperature is 2-4 hours.

Preferably, the mass concentration of the bovine serum albumin solution in S2 of step (2) is 1%, and the amount dropped on the surface of the activated gold electrode is 10-20 μL; the time left at room temperature is 1-2 hours.

Preferably, the acetamiprid concentration in S3 of step (2) is 0-10 mg/kg; the dosage ratio of the acetamiprid standard sample to the acetamiprid aptamer-modified zirconium-based metal-organic framework is (10 ~15)mL: (1~2)g; the time for stirring and enriching is 10~20 minutes; the time for standing still is 10~20 seconds.

Preferably, the pH of the phosphate buffer in S4 of step (2) is 7.2-7.5, and the volume of the flushing working electrode is 1-2ml; the volume after constant volume is 10mL.

Wherein, W is a specific excitation wavelength, W is greater than 0 and is a positive integer; preferably, the excitation wavelength is 365nm.

Preferably, the universal extracting solution in S3 of step (3) is the universal extracting solution for YRSPN samples; the dosage ratio of the fruit and vegetable samples to be tested to the universal extracting solution for samples is 2-2.5 g: 5 mL.

Beneficial effects of the present invention:

The present invention first proposes to use the dual-signal characteristics of zirconium-based metal-organic frameworks for the electrochemical and fluorescence rapid detection of acetamiprid in fruits and vegetables, and realizes the dual-mode detection of acetamiprid by a single nanomaterial for the first time.

The dual-mode detection of acetamiprid proposed by the present invention can reduce or eliminate low detection accuracy or false positive results caused by external factors such as substrate concentration, external environment and instrument conditions. The correlation coefficients of the electrochemical and fluorescence correlation prediction models were 0.998 and 0.997, respectively.

The specific recognition of acetamiprid by the acetamiprid aptamer proposed by the present invention greatly improves the selectivity and accuracy of the nanoprobe in a complex system.

The invention simplifies the manufacture of the dual-mode nano sensor sensing system, and further reduces the detection error caused by the stability of the sensing system (the relative error of the detection result compared with the national standard method is less than 1%).

Description of drawings

Figure 1 is a characteristic diagram of the morphology of zirconium-based metal-organic frameworks.

Fig. 2 is a diagram of the electrochemical signal (a) and the fluorescence signal (b) of the zirconium-based metal-organic framework.

specific implementation plan

The present invention will be described in detail through various embodiments below. However, these examples are only for illustrating the present invention and are not intended to limit the scope of the present invention. In addition, after reading the contents of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

The gold electrodes used in the present invention were purchased from Shanghai Lushuo Industrial Co., Ltd., and the remaining reagents were purchased from Sinopharm Chemical Reagent Co., Ltd.

A method for rapid detection of acetamiprid dual modes in fruits and vegetables, comprising the following steps:

(1) Preparation of zirconium-based metal-organic frameworks

S1. Dissolve zirconium tetrachloride and 2-aminoterephthalic acid in 20mL of N,N-dimethylformamide, the amount of zirconium tetrachloride and 2-aminoterephthalic acid is 0.2mol; Shake for 10 minutes, move to a magnetic stirrer, add 5 mL of glacial acetic acid, continue to stir and mix for 10 minutes, transfer the mixed solution to a 50 mL reaction kettle; The framework was washed twice with N,N-dimethylformamide and twice with methanol, and dried in a vacuum oven to obtain a purified zirconium-based metal-organic framework.

S2. Acetamiprid aptamer modified zirconium-based metal-organic framework, 100 μmol/L acetamiprid aptamer (5'-(COOH)-(CH2)6-ACA GGC TAC GAG GGA AAT GCG GTG GGT GTG GGC GAT -3') solution 1mL mixed with 0.1mmol/L EDC solution 5mL and 0.1mmol/L NHS solution 5mL, stirred and incubated at room temperature for 2 hours to activate the carboxyl group; then added 1.5g of the zirconium-based metal-organic framework obtained above, Incubate at room temperature for 12 hours to obtain acetamiprid aptamer-modified zirconium-based metal-organic frameworks.

(2) Acquisition of electrochemical signals

Electrode pretreatment: Polish the gold electrode with alumina powder with a particle size of 1.0 μm, 0.3 μm, and 0.05 μm in sequence, polish and polish on a polishing flannelette for 5 minutes, and then ultrasonically clean the residue in absolute ethanol and deionized water for 5 minutes respectively Dry the aluminum oxide with nitrogen; carry out cyclic potential scanning in 0.5mol/L dilute sulfuric acid, observe its oxidation and reduction peak potentials, until the oxidation and reduction peaks completely overlap, which means that the surface of the gold electrode has been cleaned, and an activated gold electrode is obtained. ;

Gold electrode acetamiprid aptamer complementary strand modification: 5 μL of 100 μmol/L acetamiprid aptamer complementary strand (5'-(SH)-(CH2)6-TGT CCG ATG CTC-3') solution was added dropwise On the surface of the activated gold electrode, incubate at room temperature for 3 hours, and wash the unbound acetamiprid aptamer complementary chain on the surface with deionized water. 20 μL of BSA with a mass concentration of 1% was titrated, left at room temperature for 1 hour, and the surface of the electrode was rinsed with deionized water to obtain a gold electrode modified with the complementary chain of the acetamiprid aptamer.

Determination by pulse voltammetry: prepare standard samples of acetamiprid with different concentrations, wherein the concentrations of acetamiprid are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10mg/kg, in the standard 1.5 g of acetamiprid aptamer-modified zirconium-based metal-organic frameworks were added to the sample. Insert the gold electrode modified by the acetamiprid aptamer complementary chain into the above mixed solution, and stir to make the acetamiprid aptamer complementary chain modified on the gold electrode adapt to the acetamiprid modified on the zirconium-based metal-organic framework. The body bases are complementary paired and combined, and the zirconium-based metal-organic framework is enriched on the surface of the gold electrode. The enrichment process lasts for 15 minutes, and the working electrode is obtained; after the enrichment is completed, the stirring is stopped, and the solution is allowed to stand for 15 seconds; the electrical signal acquisition stage: The potential of the working electrode was scanned from 1.2V to 0.5V. During this process, the zirconium-based metal-organic framework was attached to the surface of the gold electrode to form a stripping current. The electrical signal intensity at different concentrations of acetamiprid was measured and recorded by an electrochemical workstation: 21.782, 18.987 , 17.056, 15.71, 13.227, 11.057, 9.315, 7.1352, 5.2454, 3.189, 0.987 mA.

(3) Acquisition of fluorescent signals

Take out the working electrode in the above step (2), take 1mL of phosphate buffer solution to rinse the surface of the electrode, collect the rinse solution and the solution in the above step (2) and dilute to 10mL, take 2mL in a quartz cuvette , set the excitation wavelength of the fluorescence spectrometer to 365nm, measure and record the best fluorescence emission intensity of the mixed solution under different concentrations of acetamiprid standard samples: .

(4) Rapid prediction of the concentration of acetamiprid

Electrochemical rapid detection prediction model: the electrochemical signals 21.782, 18.987, 17.056, 15.71, 13.227, 11.057, 9.315, 7.1352, 5.2454, 3.189, 0.987 mA obtained in the above step (2) were compared with different concentrations of acetamiprid standards Models were established for samples 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mg/kg. The electrochemical rapid detection prediction model E=-2.033X+21.411 (R ² =0.998) of acetamiprid was obtained;

Fluorescence rapid detection prediction model: the fluorescence signals obtained in the above step (3) 199.74, 248.56, 315.71, 361.24, 428.79, 479.56, 516.91, 597.16, 668.25, 719.53, 787.15 with different concentrations of acetamiprid standard samples 0, 1 , 2, 3, 4, 5, 6, 7, 8, 9, and 10 mg/kg were used to establish models, and the prediction model for rapid fluorescence detection of acetamiprid was obtained as F=58.532X+191.21 (R ² =0.997).

Example 1: Rapid prediction of acetamiprid concentration in apples

Weigh 5 apple samples to be tested (2.05g, 2.12g, 2.09g, 2.06g, 2.15g), add the shredded or crushed samples into a 10mL centrifuge tube; add 5mL YRSPN sample for general extraction solution, fully vortexed and mixed, that is, the solution to be tested.

Take 2mL of the solution to be tested and add acetamiprid aptamer-modified zirconium-based metal-organic frameworks to obtain fluorescence signals and electrochemical signals, respectively, and repeat the measurement three times. The results are shown in Table 1. The results of SPSS analysis show that there is a significant difference in the measurement results of the fluorescence method and the electrochemical method in the fourth group of samples, indicating that there are problems in the data, so this group of data is considered invalid data and discarded; If there is no significant difference among the data of the 5 groups, the average concentration of acetamiprid in apples is 0.466mg/kg, 1.074mg/kg, 1.553mg/kg, 2.471mg/kg respectively. In order to verify the detection accuracy of the method of the present invention, the national standard method (GB/T23584-2009) is used to analyze the acetamiprid concentration of the 1st, 2nd, 3rd, and 5th group samples, and the obtained acetamiprid concentrations are respectively 0.462 mg/kg, 1.068mg/kg, 1.541mg/kg, 2.465mg/kg. The relative error of the obtained detection result is less than 1%, which shows that the method for rapid detection of acetamiprid in a kind of fruits and vegetables in the present invention further reduces the detection error caused by the stability problem of the sensing system and improves the detection efficiency. accuracy.

Table 1. Determination of acetamiprid content in apples by fluorescence and electrochemical methods

Embodiment 2: rapid prediction of acetamiprid concentration in cherry tomatoes

Weigh 5 parts of cherry tomatoes to be tested, respectively (2.03g, 2.02g, 2.06g, 2.09g, 2.11g), add the shredded or crushed samples into a 10mL centrifuge tube; add 5mL YRSPN sample Universal extract, fully oscillated and mixed, is the solution to be tested.

Take 2 mL of the liquid to be tested and add zirconium-based metal-organic frameworks, respectively, to obtain fluorescence signals and electrochemical signals, and repeat the measurement three times. The results of the concentration of acetamiprid obtained by the rapid prediction model of the fluorescence method and the electrochemical method are shown in Table 2. The SPSS analysis results show that there are significant differences in the measurement results of the fluorescence method and the electrochemical method in the first group of samples, indicating that there is a problem with the data, then this group of data is considered invalid data and discarded; the second, third, and fourth , There is no significant difference between the data of the 5 groups, then the average concentration of acetamiprid in the cherry tomatoes is 2.312mg/kg, 3.476mg/kg, 4.683mg/kg, 5.366mg/kg respectively. In order to verify the detection accuracy of the method of the present invention, utilize national standard method (GB/T 23584-2009) to carry out acetamiprid concentration analysis to the 2nd, 3, 4, 5 groups of samples, the obtained acetamiprid concentration is respectively 2.324mg/kg, 3.469mg/kg, 4.655mg/kg, 5.357mg/kg. The relative error of the obtained detection result is less than 1%, which shows that the method for rapid detection of acetamiprid in a kind of fruits and vegetables in the present invention further reduces the detection error caused by the stability problem of the sensing system and improves the detection efficiency. accuracy.

Table 2. Determination of acetamiprid content in cherry tomatoes by fluorescence method and electrochemical method

Explanation: the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention; therefore, although the specification has described the present invention in detail with reference to the above-mentioned embodiments, those of ordinary skill in the art should It is understood that the present invention can still be modified or equivalently replaced; and all technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims (10)

1. A method for rapid detection of acetamiprid dual modes in fruits and vegetables, characterized in that the specific steps are as follows: (1) Preparation of zirconium-based metal-organic frameworks S1. Dissolve zirconium tetrachloride and 2-aminoterephthalic acid in N,N-dimethylformamide, mix them with ultrasonic vibration, add glacial acetic acid, continue to stir to obtain a mixed solution, transfer it to a reaction kettle, and The reaction is carried out under a certain temperature condition, and after the reaction, the product is washed several times with N,N-dimethylformamide and methanol successively, and dried in a vacuum drying oven to obtain a purified zirconium-based metal-organic framework; S2. Acetamiprid aptamer modification of zirconium-based metal-organic frameworks: the acetamiprid aptamer solution was mixed with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and N- Mix hydroxysuccinimide, stir and incubate at room temperature, add the zirconium-based metal-organic framework purified in step S1, incubate at room temperature, and then centrifuge the product, and the obtained solid precipitate is the acetamiprid aptamer-modified zirconium based metal-organic frameworks; (2) Acquisition of electrochemical and fluorescent signals S1. Electrode pretreatment: Polish the gold electrode with alumina powder of different particle sizes on the polishing flannelette, then ultrasonically treat it in absolute ethanol and deionized water, and dry it with nitrogen; then place it in sulfuric acid solution for cyclic potential Scan and observe its oxidation and reduction peak potentials until the oxidation and reduction peaks completely overlap to obtain an activated gold electrode; S2. Gold electrode acetamiprid aptamer complementary chain modification: Add the acetamiprid aptamer complementary chain solution dropwise on the surface of the activated gold electrode described in S1 of step (2), and rinse with deionized water after incubation at room temperature Rinse the unbound acetamiprid aptamer complementary chain solution on the surface; then add bovine serum albumin solution dropwise, and rinse the electrode surface with deionized water after standing for a period of time at room temperature to obtain the gold modified by the acetamiprid aptamer complementary chain. electrode; S3. Determination by pulse voltammetry: Prepare standard samples of acetamiprid with different concentrations, which are respectively recorded as C ₁ , C ₂ ,...,C _n-1 , C _n , where n is a positive integer; Add the zirconium-based metal-organic framework modified by the acetamiprid aptamer obtained in S2 of step (1) to obtain a mixed solution; the acetamiprid aptamer complementary chain modified gold obtained in S2 of step (2) The electrode is inserted into the above mixed solution, stirred and enriched for a period of time, so that the zirconium-based metal-organic framework modified by the acetamiprid aptamer is connected to the gold electrode modified by the complementary chain of the acetamiprid aptamer through complementary base pairing; After completion, stop stirring and let the solution stand for a period of time. During this process, the zirconium-based metal-organic framework modified by the acetamiprid aptamer is attached to the surface of the gold electrode modified by the complementary chain of the acetamiprid aptamer, and the working electrode is obtained; S4. Electric signal acquisition stage: carry out potential scanning to the working electrode described in S3 of step (2), the potential scans from 1.2V to 0.5V, obtains the electrical signal of the working electrode, uses the working electrode to measure and record different concentrations of acetidine The electrical signal intensity of the amidine standard sample is recorded as E ₁ , E ₂ ,..., E _n-1 , E _n , where n is a positive integer; S5. Fluorescence signal acquisition stage: After measuring the electrical signal intensity of acetamiprid standard sample of a concentration, take out the working electrode and rinse the surface of the working electrode with phosphate buffer, and collect and wash the phosphate buffer of this concentration. Acetamiprid standard samples are mixed; after this operation, a mixture of different concentrations of acetamiprid standard samples and the washed phosphate buffer solution will be obtained. Put it into a quartz cuvette, set the excitation wavelength of the fluorescence spectrometer, measure and record its optimal fluorescence emission intensity, denoted as F ₁ , F,...,F _n-1 ,F _n , where n is a positive integer; (3) Rapid detection of acetamiprid concentration S1. Electrochemical rapid detection prediction model: according to the electrical signal intensity E ₁ , E ₂ ,..., E _n-1 , E n described in S4 of step (2), E _n and different concentrations of acetamiprid standard samples C ₁ ,C ₂ ,...,C _n-1 ,C _n establishes a model to obtain the electrochemical rapid detection prediction model E=f(X) of acetamiprid, where E is the electrochemical current, X is the concentration of acetamiprid, n is a positive integer; S2. Fluorescence rapid detection prediction model: compare the fluorescence emission intensities F ₁ , F, ... , F _n-1 , F _n described in S5 of step (2) with different concentrations of acetamiprid standard samples C ₁ , C ₂ ,...,C _n-1 ,C _n establishes a model, and obtains acetamiprid's fluorescence rapid detection prediction model F=f(X), wherein F is the fluorescence emission intensity, X is the concentration of acetamiprid, and n is a positive integer ; S3. Rapid prediction of the concentration of acetamiprid in fruits and vegetables: Take the fruit and vegetable samples to be tested and cut them into pieces or grind them into pieces, then add the general extract of the samples, fully oscillate and mix, and then it is the solution to be tested; follow steps (2) in S4 and S5 The method of measuring electrochemical signal and fluorescence signal obtains electrical signal intensity and fluorescence emission intensity respectively, and substitutes them into electrochemical rapid detection prediction model and fluorescence rapid detection prediction model respectively, namely obtains acetamiprid rapid detection by electrochemical method and fluorescence method. Predicted concentration value; the rapid predicted concentration value of acetamiprid determined by electrochemical method and fluorescence method was analyzed by SPSS for difference between groups; if there is a significant difference between the two groups of data, the data will be discarded; if there is no difference between the two groups of data If there is a significant difference, the average value of the above data is taken as the concentration of acetamiprid in fruits and vegetables, so as to realize the rapid detection of the concentration of acetamiprid. 2. the method for rapid detection of acetamiprid in fruits and vegetables according to claim 1, is characterized in that the mol ratio of zirconium tetrachloride and 2-aminoterephthalic acid described in S1 of step (1) It is 1:1; the concentration of the zirconium tetrachloride and 2-aminoterephthalic acid in the mixed solution is 8mmol L ^-1 ; the volume ratio of the N,N-dimethylformamide and glacial acetic acid 4:1; the time for the ultrasonic oscillation and mixing is 5-10 minutes; the reaction temperature in the reactor is 110-150°C, and the time is 8-15 hours; the cleaning times are 1-4 times . 3. the method for rapid detection of acetamiprid dual modes in fruits and vegetables according to claim 1, is characterized in that, described in the S2 of step (1) acetamiprid aptamer solution, 1-(3-dimethyl Aminopropyl)-3-ethylcarbodiimide hydrochloride, N-hydroxysuccinimide and purified zirconium-based metal-organic framework are used in a ratio of 1mL:5mL:5mL:1-2g; the acetamiprid The concentration of the aptamer solution is 100 μmol/L; the concentration of the 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride is 0.1mmol/L; the N-hydroxysuccinate The concentration of imide is 0.1mmol/L; the base sequence of the acetamiprid aptamer is: 5'-(COOH)-(CH2)6-ACA GGC TAC GAG GGAAAT GCG GTG GGT GTG GGC GAT-3 '. 4. the method for rapid detection of acetamiprid dual-mode in fruits and vegetables according to claim 1, is characterized in that, the time of stirring and hatching described in the S2 of step (1) is 1～2 hour; Add purified zirconium base The incubation time after MOF is 10-12 hours. 5. the method for rapid detection of acetamiprid dual-mode in fruits and vegetables according to claim 1, is characterized in that, the particle diameter of the aluminum oxide powder of different particle diameter described in the S1 of step (2) is successively 1.0 μm, 0.3 μm, 0.05 μm, the grinding time is 3-5 minutes; the ultrasonic treatment time is 3-5 minutes; the concentration of the sulfuric acid solution is 0.5mol/L. 6. the method for rapid detection of acetamiprid dual-mode in fruits and vegetables according to claim 1, is characterized in that, the base sequence of acetamiprid aptamer complementary chain described in the S2 of step (2) is: 5. '-(SH)-(CH2)6-TGT CCG ATG CTC-3'; the concentration of the acetamiprid aptamer complementary chain solution is 100 μmol/L, and the amount dropped on the surface of the activated gold electrode is 5-10 μL ; The incubation time at normal temperature is 2 to 4 hours. 7. the method for rapid detection of acetamiprid dual-mode in fruits and vegetables according to claim 1, is characterized in that, the mass concentration of bovine serum albumin solution described in the S2 of step (2) is 1%, drips in activated The amount used on the surface of the gold electrode is 10-20 μL; the time for standing at room temperature is 1-2 hours. 8. The method for rapid detection of acetamiprid in fruits and vegetables according to claim 1, wherein the concentration of acetamiprid in S3 of step (2) is 0 to 10 mg/kg; The ratio of the amidine standard sample to the zirconium-based metal-organic framework modified by the acetamiprid aptamer is (10-15) mL: (1-2) g; the time for stirring and enriching is 10-20 minutes; The standing time is 10-20 seconds. 9. the method for rapid detection of acetamiprid dual-mode in fruits and vegetables according to claim 1, is characterized in that, the pH of the phosphate buffer solution described in the S4 of step (2) is 7.2～7.5, and the pH of washing working electrode The volume is 1-2ml; the volume after constant volume is 10mL. 10. the method for rapid detection of acetamiprid in fruits and vegetables according to claim 1, is characterized in that, the general extracting solution described in the S3 of step (3) is the general extracting solution of YRSPN sample; The fruit and vegetable to be tested The dosage ratio of sample to sample universal extract is 2-2.5g:5mL.

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