A method for rapid detection of pesticide residues in sour jujube seed slices

Abstract

The present invention discloses a method for rapidly detecting residual pesticides in Chinese jujube seed slices, comprising the following steps: (1) treating Chinese jujube seed slices to obtain a liquid to be tested; (2) preparing a nanosilver-doped polyaniline composite material; (3) applying the nanosilver-doped polyaniline composite material dropwise to the activated active part of a glassy carbon electrode, and drying it at room temperature to obtain a modified glassy carbon electrode; (4) subjecting the modified glassy carbon electrode to a cyclic voltammetry scan in a phosphate buffer solution containing the liquid to be tested, and the residual pesticides in the Chinese jujube seed slices can be directly detected by the oxidation peak current value. The advantage of the present invention is that the Chinese jujube seed slices only need to be simply treated, and then electrochemical detection can be performed by the modified electrode, and the residual pesticides in the Chinese jujube seed slices can be directly detected by the oxidation peak current value, and a simple judgment of the content can be performed.

Description

Technical Field

[0001] The invention relates to the technical field of pesticide residue detection, and in particular to a method for rapidly detecting pesticide residues in sour jujube seed decoction pieces. Background Art

[0002] The rapid development of modern agriculture has led to an increasing output of agricultural products. However, while ensuring the output of agricultural products, a large amount of pesticides, antibiotics and hormones have been used in the production of agricultural products, resulting in excessive pesticide residues in products such as vegetables, fruits, grains, and Chinese medicinal materials, becoming a major hidden danger to consumers' food safety.

[0003] Suanzaoren, also known as jujube kernel, jujube kernel, and mountain jujube kernel. It is made by removing the pulp and shell of the mature fruit of the Rhamnaceae tree jujube, collecting the seeds, and drying them. It grows on sunny slopes and roadsides, and is mainly produced in Henan, Hebei, Shaanxi, Liaoning, Shanxi, Shandong, Yunnan and other places. It is harvested when the fruit is ripe in autumn, and the pulp and hard core are removed, and the seeds are taken out, which can be used raw or slightly fried. Suanzaoren is the seed of jujube, which can be used as medicine after processing. It contains alkaloids, multiple amino acids and metal elements, which can calm the mind, nourish the liver, and astringe sweat. It has a good therapeutic effect on symptoms such as insomnia, palpitations, and spontaneous sweating due to physical weakness. Suanzaoren is often used in combination with Ganoderma lucidum, which has the effects of calming the mind and helping sleep, and can treat severe insomnia.

[0004] Pyrethroid pesticides are a broad-spectrum insecticide. Due to their low price and high efficacy, pyrethroid pesticides are widely used in the pest control process of the growth of jujube seeds. These pesticides are neurotoxic. Long-term exposure to pyrethroid pesticides can cause headaches, dizziness, nausea, vomiting, upper abdominal burning pain, fatigue, loss of appetite, chest tightness, salivation, etc. Therefore, it is very important to safely and efficiently detect the pyrethroid pesticide residues in the prepared jujube seeds.

[0005] Regardless of whether it is economical, real-time on-site rapid testing or routine testing using large instruments in the laboratory, complex operating steps are required, which is of no help when real-time rapid testing of pesticide residues is required on-site. Summary of the invention

[0006] The purpose of the present invention is to provide a method for quickly detecting residual pesticides in Chinese jujube seed slices. The Chinese jujube seed slices only need to be simply processed and then electrochemical detection can be performed through the modified electrodes. The residual pesticides in the Chinese jujube seed slices can be intuitively detected through the oxidation peak current value, and a simple judgment of the content can be made.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions:

[0008] A method for rapidly detecting residual pesticides in Chinese date seed slices, characterized in that it comprises the following steps:

[0009] (1) After drying, the dried pieces of Semen Ziziphi Spinosae were crushed by a grinder, and then sieved. After sieving, water was added to soak the pieces overnight, and then an acetic acid acetonitrile solution was added to the pieces for ultrasonic treatment in an ice water bath. Then, anhydrous magnesium sulfate and sodium acetate were added to the pieces for vortex shaking, and then centrifuged. Anhydrous magnesium sulfate and N-propylethylenediamine were added to the supernatant, and the pieces were vortex shaken again and centrifuged. The supernatant was filtered to obtain the test solution;

[0010] (2) adding silver nanoparticles to a sulfuric acid aqueous solution of double distilled aniline and stirring the mixture; after stirring for a period of time, slowly adding a 0.1 mol / L ammonium persulfate solution and continuing to stir; after stirring, placing the mixture in an ice water bath overnight; filtering the obtained precipitate with double distilled water and methanol, and then drying the mixture in a vacuum drying oven to obtain a nanosilver-doped polyaniline composite material;

[0011] (3) The devitrified carbon electrode was ground and polished on suede containing 0.3 μm and 0.05 μm Al2O3 powder, respectively. After polishing, it was ultrasonically treated in pure water to remove the Al2O3 powder adhering to the surface. Then, a cyclic voltammetry test was performed in a potassium ferrocyanide solution. When the test result was good, the glassy carbon electrode was taken out, rinsed with ultrapure water and then dried at room temperature to obtain an activated glassy carbon electrode.

[0012] (4) Dispersing the nanosilver-doped polyaniline composite material in a 3% acetic acid solution, taking 6 μL of the dispersed nanosilver-doped polyaniline composite material with a pipette and applying it on the active part of the activated glassy carbon electrode, and drying it at room temperature to obtain a modified glassy carbon electrode;

[0013] (5) The modified glassy carbon electrode is first subjected to cyclic voltammetry scanning in phosphate buffer solution. After the voltammetric curve stabilizes, a certain volume of the test solution is added. After stirring and enriching for a period of time under fixed potential conditions, a linear voltammetric scan is performed and the oxidation peak current is recorded. The oxidation peak current value can be used to intuitively detect the residual pesticides in the Chinese jujube seed slices.

[0014] Preferably, the jujube seed slices in (1) are sieved through a 20-mesh screen after being crushed, and the supernatant is filtered using a 0.22 μm filter membrane.

[0015] Preferably, the mass ratio of the sieved Chinese jujube kernel, the anhydrous magnesium sulfate added for the first time, the sodium acetate, the anhydrous magnesium sulfate added for the second time and N-propylethylenediamine in (1) is 1:(2-3):(0.8-1.1):(0.2-0.3):(0.05-0.1), the mass concentration of the acetic acid acetonitrile solution is 1%, and the mass volume ratio of the sieved Chinese jujube kernel to the acetic acid acetonitrile solution is 1g:(15-19ml).

[0016] Preferably, the preparation method of the silver nanoparticles in (2) is as follows: polyvinyl pyrrolidone and 0.0060 mol / L silver nitrate solution are mixed and then diluted with ultrapure water, and then 0.0080 mol / L sodium borohydride solution is slowly added dropwise to the mixture, and the solution changes from colorless to orange-yellow, and then the mixture is stirred on a magnetic stirrer to form a sol, and the sol is placed in a dialysis bag for dialysis, and after the dialysis is completed, it is placed in a vacuum drying oven at 40°C to obtain silver nanoparticles.

[0017] Preferably, the mass volume ratio of the polyvinyl pyrrolidone to the silver nitrate solution, ultrapure water and sodium borohydride solution is (0.1-0.2 g): (10-12 ml): (100-130 ml): (110-130 ml).

[0018] Preferably, the mass volume ratio of the silver nanoparticles to the sulfuric acid aqueous solution of double distilled aniline and ammonium persulfate in (2) is 1 g: (10-15 ml): (7-11 ml), and the sulfuric acid aqueous solution of double distilled aniline is prepared by: dissolving 0.1 mol / L double distilled aniline in the same volume of 0.1 mol / L sulfuric acid aqueous solution, and stirring at room temperature for 10 min.

[0019] Preferably, the grinding track of the glassy carbon electrode in (3) is in the shape of an "8", and the ultrasonic treatment is performed for 3 to 5 minutes.

[0020] Preferably, the mass volume ratio of the nanosilver-doped polyaniline composite material to the 3% acetic acid solution in (4) is 1 g: (35-50 ml).

[0021] Preferably, the pH value of the phosphate buffer solution in (5) is 7.0, the volume ratio of the test solution to the phosphate buffer solution is 1:100, the enrichment time is 20-30 s, and the voltage of the linear voltammetric scan is between 0.30 V and 0.80 V.

[0022] In summary, the present invention has the following beneficial effects: the present invention modifies the surface of the glassy carbon electrode by the nanosilver-doped polyaniline composite material, and the charging current of the glassy carbon electrode in the solution is significantly increased. The modification of the nanosilver-doped polyaniline composite material can significantly increase the effective area of ​​the electrode, thereby increasing the peak current, thereby effectively improving the detection of residual pyrethroid pesticides. By pretreating the Chinese jujube seed decoction pieces in the early stage, the interference of other substances on the electrochemical detection is avoided, and the detection accuracy is higher. DETAILED DESCRIPTION

[0023] The specific implementation modes of the present invention are further described below, and these embodiments do not constitute a limitation of the present invention.

[0024] Example 1

[0025] A method for rapidly detecting pesticide residues in sour jujube seed decoction pieces comprises the following steps:

[0026] (1) After drying, the dried pieces of Chinese jujube seeds were crushed by a grinder. After the crushing, they were sieved through a 20-mesh screen. After sieving, they were soaked in water and left overnight. Subsequently, an acetic acid acetonitrile solution was added for ultrasonic treatment in an ice-water bath. Subsequently, anhydrous magnesium sulfate and sodium acetate were added for vortex shaking. After centrifugation, anhydrous magnesium sulfate and N-propylethylenediamine were added to the supernatant. After vortex shaking again, the supernatant was filtered through a 0.22 μm filter membrane to obtain a test solution. The mass ratio of the sieved Chinese jujube seeds, the anhydrous magnesium sulfate added for the first time, the sodium acetate, and the anhydrous magnesium sulfate added for the second time and N-propylethylenediamine was 1:2:0.8:0.2:0.05. The mass concentration of the acetic acid acetonitrile solution was 1%. The mass volume ratio of the sieved Chinese jujube seeds to the acetic acid acetonitrile solution was 1 g:15 ml.

[0027] (2) Mix polyvinyl pyrrolidone and 0.0060 mol / L silver nitrate solution and add ultrapure water to dilute. Then slowly add 0.0080 mol / L sodium borohydride solution to the mixture. The mass volume ratio of polyvinyl pyrrolidone to silver nitrate solution, ultrapure water and sodium borohydride solution is 0.1 g: 10 ml: 100 ml: 110 ml. The solution changes from colorless to orange-yellow. Then stir the mixture on a magnetic stirrer to form a sol. Put the sol in a dialysis bag for dialysis. After the dialysis is completed, dry it in a vacuum oven at 40°C to obtain silver nanoparticles. Take 0.1 mol / L secondary The distilled aniline was dissolved in a 0.1 mol / L sulfuric acid aqueous solution of the same volume to obtain a sulfuric acid aqueous solution of secondary distilled aniline, the sulfuric acid aqueous solution of secondary distilled aniline was added with silver nanoparticles and stirred, and stirred at room temperature for 10 minutes. After stirring for a period of time, 0.1 mol / L ammonium persulfate solution was slowly added dropwise, and the mass volume ratio of the silver nanoparticles to the sulfuric acid aqueous solution of secondary distilled aniline and ammonium persulfate was 1g:10ml:7ml. The stirring was continued, and after the stirring was completed, it was placed in an ice water bath overnight. The obtained precipitate was filtered with secondary distilled water and methanol, and then dried in a vacuum drying oven to obtain a nanosilver-doped polyaniline composite material.

[0028] (3) The devitrified carbon electrode was ground and polished on suede containing 0.3 μm and 0.05 μm Al2O3 powder, respectively, with the grinding track forming an "8" shape. After polishing, it was ultrasonically treated in pure water for 3 to 5 min to remove the Al2O3 powder adhering to the surface. Then, a cyclic voltammetry test was performed in a potassium ferrocyanide solution. When the test result was good, the glassy carbon electrode was taken out, rinsed with ultrapure water and dried at room temperature to obtain an activated glassy carbon electrode.

[0029] (4) The nanosilver-doped polyaniline composite material was dispersed in a 3% acetic acid solution. The mass volume ratio of the nanosilver-doped polyaniline composite material to the 3% acetic acid solution was 1 g:35 ml. 6 μL of the dispersed nanosilver-doped polyaniline composite material was transferred by a pipette and dropped on the active part of the activated glassy carbon electrode, and then dried at room temperature to obtain a modified glassy carbon electrode.

[0030] (5) The modified glassy carbon electrode was first subjected to cyclic voltammetry scanning in a phosphate buffer solution with a pH of 7.0. After the voltammetric curve was stabilized, the test solution was added. The volume ratio of the test solution to the phosphate buffer solution was 1:100. After stirring and enriching for 20 seconds under fixed potential conditions, a linear voltammetric scan was performed between 0.30 V and 0.80 V, and the oxidation peak current was recorded. The oxidation peak current value can be used to intuitively detect the residual pesticides in the Chinese jujube seed slices.

[0031] Example 2

[0032] A method for rapidly detecting pesticide residues in sour jujube seed decoction pieces comprises the following steps:

[0033] (1) Take the dried pieces of Chinese jujube seeds and grind them with a grinder. After grinding, sieve them with 20 mesh. After sieving, soak them in water and leave them overnight. Then, add acetic acid acetonitrile solution and ultrasonically treat them in an ice-water bath. Then, add anhydrous magnesium sulfate and sodium acetate, vortex and shake them, and then centrifuge them. Take the supernatant and add anhydrous magnesium sulfate and N-propylethylenediamine again. Vortex and shake them again and centrifuge them. Take the supernatant and filter it with a 0.22 μm filter membrane to obtain the test solution. The mass ratio of the sieved Chinese jujube seeds, the anhydrous magnesium sulfate added for the first time, sodium acetate, and the anhydrous magnesium sulfate added for the second time and N-propylethylenediamine is 1:3:1:0.2:0.08. The mass concentration of the acetic acid acetonitrile solution is 1%. The mass volume ratio of the sieved Chinese jujube seeds and the acetic acid acetonitrile solution is 1 g:17 ml.

[0034] (2) Mix polyvinyl pyrrolidone and 0.0060 mol / L silver nitrate solution and add ultrapure water to dilute. Then slowly add 0.0080 mol / L sodium borohydride solution to the mixture. The mass volume ratio of polyvinyl pyrrolidone to silver nitrate solution, ultrapure water and sodium borohydride solution is 0.2 g: 11 ml: 110 ml: 120 ml. The solution changes from colorless to orange-yellow. Then stir the mixture on a magnetic stirrer to form a sol. Put the sol in a dialysis bag for dialysis. After dialysis, dry it in a vacuum oven at 40°C to obtain silver nanoparticles. Take 0.1 mol / L secondary The distilled aniline was dissolved in a 0.1 mol / L sulfuric acid aqueous solution of the same volume to obtain a sulfuric acid aqueous solution of secondary distilled aniline, the sulfuric acid aqueous solution of secondary distilled aniline was added with silver nanoparticles and stirred, and stirred at room temperature for 10 minutes. After stirring for a period of time, 0.1 mol / L ammonium persulfate solution was slowly added dropwise, and the mass volume ratio of the silver nanoparticles to the sulfuric acid aqueous solution of secondary distilled aniline and ammonium persulfate was 1g:12ml:9ml, and stirring was continued. After the stirring was completed, it was placed in an ice water bath overnight, and the obtained precipitate was filtered with secondary distilled water and methanol, and then dried in a vacuum drying oven to obtain a nanosilver-doped polyaniline composite material.

[0035] (3) The devitrified carbon electrode was ground and polished on suede containing 0.3 μm and 0.05 μm Al2O3 powder, respectively, with the grinding track forming an "8" shape. After polishing, it was ultrasonically treated in pure water for 3 to 5 min to remove the Al2O3 powder adhering to the surface. Then, a cyclic voltammetry test was performed in a potassium ferrocyanide solution. When the test result was good, the glassy carbon electrode was taken out, rinsed with ultrapure water and dried at room temperature to obtain an activated glassy carbon electrode.

[0036] (4) The nanosilver-doped polyaniline composite material was dispersed in a 3% acetic acid solution. The mass volume ratio of the nanosilver-doped polyaniline composite material to the 3% acetic acid solution was 1 g:42 ml. 6 μL of the dispersed nanosilver-doped polyaniline composite material was transferred by a pipette and dropped on the active part of the activated glassy carbon electrode, and then dried at room temperature to obtain a modified glassy carbon electrode.

[0037] (5) The modified glassy carbon electrode was first subjected to cyclic voltammetry scanning in a phosphate buffer solution with a pH of 7.0. After the voltammetric curve was stabilized, the test solution was added. The volume ratio of the test solution to the phosphate buffer solution was 1:100. After stirring and enriching for 25 seconds under fixed potential conditions, a linear voltammetric scan was performed between 0.30 V and 0.80 V, and the oxidation peak current was recorded. The oxidation peak current value can be used to intuitively detect the residual pesticides in the Chinese jujube seed slices.

[0038] Example 3

[0039] A method for rapidly detecting pesticide residues in sour jujube seed decoction pieces comprises the following steps:

[0040] (1) Take the dried pieces of Chinese jujube seeds and grind them with a grinder. After grinding, sieve them with 20 mesh. After sieving, soak them in water and leave them overnight. Then, add acetic acid acetonitrile solution and ultrasonically treat them in an ice-water bath. Then, add anhydrous magnesium sulfate and sodium acetate, vortex and shake them, and then centrifuge them. Take the supernatant and add anhydrous magnesium sulfate and N-propylethylenediamine again. Vortex and shake them again and centrifuge them. Take the supernatant and filter it with a 0.22 μm filter membrane to obtain the test solution. The mass ratio of the sieved Chinese jujube seeds, the anhydrous magnesium sulfate added for the first time, sodium acetate, and the anhydrous magnesium sulfate added for the second time and N-propylethylenediamine is 1:3:1.1:0.3:0.1. The mass concentration of the acetic acid acetonitrile solution is 1%. The mass volume ratio of the sieved Chinese jujube seeds and the acetic acid acetonitrile solution is 1 g:19 ml.

[0041] (2) Mix polyvinyl pyrrolidone and 0.0060 mol / L silver nitrate solution and add ultrapure water to dilute. Then slowly add 0.0080 mol / L sodium borohydride solution dropwise to the mixture. The mass volume ratio of polyvinyl pyrrolidone to silver nitrate solution, ultrapure water and sodium borohydride solution is 0.2 g: 12 ml: 130 ml: 130 ml. The solution changes from colorless to orange-yellow. Then stir the mixture on a magnetic stirrer to form a sol. Put the sol in a dialysis bag for dialysis. After dialysis, dry it in a vacuum oven at 40°C to obtain silver nanoparticles. Take 0.1 mol / L secondary distillation. The second distilled aniline was dissolved in a 0.1 mol / L sulfuric acid aqueous solution of the same volume to obtain a sulfuric acid aqueous solution of secondary distilled aniline, the sulfuric acid aqueous solution of secondary distilled aniline was added with silver nanoparticles and stirred, and stirred at room temperature for 10 minutes. After stirring for a period of time, 0.1 mol / L ammonium persulfate solution was slowly added dropwise, and the mass volume ratio of the silver nanoparticles to the sulfuric acid aqueous solution of secondary distilled aniline and ammonium persulfate was 1g:15ml:11ml, and stirring was continued. After the stirring was completed, it was placed in an ice water bath overnight, and the obtained precipitate was filtered with secondary distilled water and methanol, and then dried in a vacuum drying oven to obtain a nanosilver-doped polyaniline composite material.

[0042] (3) The devitrified carbon electrode was ground and polished on suede containing 0.3 μm and 0.05 μm Al2O3 powder, respectively, with the grinding track forming an "8" shape. After polishing, it was ultrasonically treated in pure water for 3 to 5 min to remove the Al2O3 powder adhering to the surface. Then, a cyclic voltammetry test was performed in a potassium ferrocyanide solution. When the test result was good, the glassy carbon electrode was taken out, rinsed with ultrapure water and dried at room temperature to obtain an activated glassy carbon electrode.

[0043] (4) The nanosilver-doped polyaniline composite material was dispersed in a 3% acetic acid solution. The mass volume ratio of the nanosilver-doped polyaniline composite material to the 3% acetic acid solution was 1 g:50 ml. 6 μL of the dispersed nanosilver-doped polyaniline composite material was transferred by a pipette and dropped on the active part of the activated glassy carbon electrode, and then dried at room temperature to obtain a modified glassy carbon electrode.

[0044] (5) The modified glassy carbon electrode was first subjected to cyclic voltammetry scanning in a phosphate buffer solution with a pH of 7.0. After the voltammetric curve was stabilized, the test solution was added. The volume ratio of the test solution to the phosphate buffer solution was 1:100. After stirring and enriching for 30 seconds under fixed potential conditions, a linear voltammetric scan was performed between 0.30 V and 0.80 V, and the oxidation peak current was recorded. The oxidation peak current value can be used to intuitively detect the residual pesticides in the Chinese jujube seed slices.

[0045] The present invention modifies the surface of a glassy carbon electrode by using a nanosilver-doped polyaniline composite material, and the charging current of the glassy carbon electrode in a solution is significantly increased. The modification of the nanosilver-doped polyaniline composite material can significantly increase the effective area of ​​the electrode, thereby increasing the peak current, thereby effectively improving the detection of residual pyrethroid pesticides. By pretreating the jujube seed decoction pieces in the early stage, the interference of other substances with the electrochemical detection is avoided, and the detection accuracy is higher.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions should also be deemed to fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for rapid detection of pesticide residues in spiny jujube seed slices, characterized in that: The steps include: (1) After drying, the dried pieces of Semen Ziziphi Spinosae were crushed by a grinder, and then sieved. After sieving, water was added to soak the pieces overnight, and then an acetic acid acetonitrile solution was added to the pieces for ultrasonic treatment in an ice water bath. Then, anhydrous magnesium sulfate and sodium acetate were added to the pieces for vortex shaking, and then centrifuged. Anhydrous magnesium sulfate and N-propylethylenediamine were added to the supernatant, and the pieces were vortex shaken again and centrifuged. The supernatant was filtered to obtain the test solution; (2) adding silver nanoparticles to a sulfuric acid aqueous solution of double distilled aniline and stirring the mixture; after stirring for a period of time, slowly adding a 0.1 mol / L ammonium persulfate solution and continuing to stir; after stirring, placing the mixture in an ice water bath overnight; filtering the obtained precipitate with double distilled water and methanol, and then drying the mixture in a vacuum drying oven to obtain a nanosilver-doped polyaniline composite material; (3) A glassy carbon electrode was ground and polished on suede containing 0.3 μm and 0.05 μm Al2O3 powder, respectively. After polishing, the electrode was ultrasonically treated in pure water to remove the Al2O3 powder adhering to the surface. Then, a cyclic voltammetry test was performed in a potassium ferrocyanide solution. When the test result was good, the glassy carbon electrode was taken out, rinsed with ultrapure water, and then dried at room temperature to obtain an activated glassy carbon electrode. (4) Dispersing the nanosilver-doped polyaniline composite material in a 3% acetic acid solution, taking 6 μL of the dispersed nanosilver-doped polyaniline composite material with a pipette and applying it on the active part of the activated glassy carbon electrode, and drying it at room temperature to obtain a modified glassy carbon electrode; (5) The modified glassy carbon electrode is first subjected to cyclic voltammetry scanning in a phosphate buffer solution. After the voltammetry curve is stable, a certain volume of the test solution is added. After stirring and enriching for a period of time under fixed potential conditions, a linear voltammetry scanning is performed and the oxidation peak current is recorded. The oxidation peak current value can be used to intuitively detect the residual pesticides in the Chinese date seed slices; In the step (1), the mass ratio of the sieved Chinese jujube seeds, the anhydrous magnesium sulfate added for the first time, the sodium acetate, the anhydrous magnesium sulfate added for the second time and N-propylethylenediamine is 1:(2-3):(0.8-1.1):(0.2-0.3):(0.05-0.1), the mass concentration of the acetic acid acetonitrile solution is 1%, and the mass volume ratio of the sieved Chinese jujube seeds to the acetic acid acetonitrile solution is 1g:(15-19ml); In the step (2), the mass volume ratio of the silver nanoparticles to the sulfuric acid aqueous solution of double distilled aniline and ammonium persulfate is 1 g: (10-15 ml): (7-11 ml). The sulfuric acid aqueous solution of double distilled aniline is prepared by dissolving 0.1 mol / L double distilled aniline in the same volume of 0.1 mol / L sulfuric acid aqueous solution and stirring at room temperature for 10 min.

2. A method for rapid detection of pesticide residues in spiny jujube seeds according to claim 1, characterized in that: In the step (1), the jujube seed slices are sieved through a 20-mesh screen after being crushed, and the supernatant is filtered using a 0.22 μm filter membrane.

3. A method for rapid detection of pesticide residues in spiny jujube seed slices according to claim 1, characterized in that: The preparation method of the silver nanoparticles in step (2) is as follows: polyvinyl pyrrolidone and 0.0060 mol / L silver nitrate solution are mixed and then diluted with ultrapure water, and then 0.0080 mol / L sodium borohydride solution is slowly added dropwise to the mixture, and the solution changes from colorless to orange-yellow, and then the mixture is stirred on a magnetic stirrer to form a sol, and the sol is placed in a dialysis bag for dialysis, and after the dialysis is completed, it is dried in a vacuum drying oven at 40°C to obtain silver nanoparticles.

4. A method for rapid detection of pesticide residues in spiny jujube seed slices according to claim 3, characterized in that: The mass volume ratio of the polyvinyl pyrrolidone to the silver nitrate solution, ultrapure water and sodium borohydride solution is (0.1-0.2 g): (10-12 ml): (100-130 ml): (110-130 ml).

5. A method for rapid detection of pesticide residues in spiny jujube seed slices according to claim 1, characterized in that: In the step (3), the grinding track of the glassy carbon electrode is in the shape of an "8", and the ultrasonic treatment is performed for 3 to 5 minutes.

6. A method for rapid detection of pesticide residues in spiny jujube seeds according to claim 1, characterized in that: In the step (4), the mass volume ratio of the nanosilver-doped polyaniline composite material to the 3% acetic acid solution is 1 g: (35-50 ml).

7. A method for rapid detection of pesticide residues in spiny jujube seeds according to claim 1, characterized in that: In the step (5), the pH value of the phosphate buffer solution is 7.0, the volume ratio of the test solution to the phosphate buffer solution is 1:100, the enrichment time is 20-30 s, and the voltage of the linear voltammetric scan is between 0.30 V and 0.80 V.