A purification structure and purification method for 77 fungal toxins

Abstract

This invention discloses a purification structure and method for 77 kinds of mycotoxins, belonging to the field of detection technology. The purification structure includes a frame with an extraction tube, a salt-filled bottle, and a purification column mounted on it. The extraction tube and purification column are located on opposite sides of the frame. The salt-filled bottle is positioned on the frame between the extraction tube and the purification column. The purification column includes a filter column with a one-way valve at its end. The purification method includes the following steps: S1. Weigh a sample containing multiple mycotoxins, add it to the extraction tube for salt-filled purification, add an acetonitrile aqueous solution containing formic acid for sample extraction, allow to stand, centrifuge, and collect the supernatant; S2. Add the supernatant from step S1 to the salt-filled bottle for salt purification to obtain a purified solution; S3. Add the purified solution from step S1 to the purification column for further purification with packing material to obtain the test solution. The purification column structure of this invention provides efficient and rapid purification, significantly shortening the purification time. This method is applicable to food samples with different matrices, has a wide range of applications, and provides good purification results.

Description

Technical Field

[0001] This invention belongs to the field of detection technology, specifically relating to a purification structure and purification method for 77 kinds of fungal toxins. Background Technology

[0002] Fungal toxins are toxic small-molecule secondary metabolites produced by various fungi. They are characterized by their wide range of pollution and high toxicity, causing contamination of crops, plants and their by-products, and thus posing a serious threat to the health and safety of humans and animals.

[0003] Current research has identified approximately 500 different mycotoxins with varying chemical structures. Among the mycotoxins that pose significant risks to grains, dairy products, beverages, and fresh produce are aflatoxin, ochratoxin, trichothecotoxins, Alternaria toxins, ergot alkaloids, fumonisins, enzoiformis toxins, zearalenone, and their derivatives. Typically, contaminated crops are attacked by one or more fungi, resulting in the production of multiple mycotoxins. The synergistic effect between these toxins further exacerbates their harmfulness.

[0004] Currently, commonly used methods for detecting mycotoxins in food mainly fall into two categories. One category is analytical techniques based on immunological analysis, such as enzyme-linked immunosorbent assay (ELISA) kits and fluorescence immunoassay, which are rapid and convenient but suffer from false positives and poor repeatability, and can be used for screening one or a few mycotoxins. The other category is analytical methods represented by chromatography and mass spectrometry, such as liquid chromatography and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS / MS), which have the advantages of high sensitivity and accuracy. However, for the detection of multiple mycotoxins, HPLC-MS / MS is still the primary method. This method, based on chromatographic separation, utilizes the high sensitivity and selectivity of mass spectrometry for qualitative and quantitative detection of compounds, resulting in more accurate results. However, the complex and diverse food matrices present challenges to mass spectrometry analysis, usually requiring complex pretreatment and purification methods to achieve the goal of separating and enriching analytes and eliminating matrix interference. Methods for simultaneously purifying multiple mycotoxins remain a research challenge and hot topic in the field of mycotoxin detection.

[0005] The most widely used method for purifying multiple toxins is currently dispersion solid-phase extraction (QuEChERS), which consists of extraction, salting out, purification, and concentration steps. While flexible and efficient, this method is relatively cumbersome and time-consuming. Building upon this technology, the inventors have developed a more convenient and effective method for purifying multiple toxins, capable of simultaneously purifying 77 common mycotoxins. This provides technical support for the subsequent nationwide detection, supervision, and control of mycotoxins in food safety. Summary of the Invention

[0006] This invention provides a purification structure and purification method for 77 kinds of mycotoxins to solve the above-mentioned technical problems.

[0007] To solve the above technical problems, the present invention adopts the following technical solution:

[0008] A purification structure for 77 fungal toxins includes a frame on which an extraction tube, a salt bottle, and a purification column are mounted.

[0009] The extraction tube and the purification column are respectively located on both sides of the fixing frame;

[0010] The salt bottle is mounted on the mounting bracket in the area between the extraction tube and the purification column;

[0011] The purification column includes a filter column, and a one-way valve is provided at the end of the filter column;

[0012] The extraction tube contains a salt pack, the salt pack bottle contains salt, and the purification column contains packing material.

[0013] A sample purification method involving 77 fungal toxins includes the following steps:

[0014] S1. Weigh a sample containing multiple fungal toxins, add it to an extraction tube, purify it with a salt pack, add an acetonitrile aqueous solution containing formic acid to extract the sample, let it stand and centrifuge, and take the supernatant.

[0015] S2. The supernatant from step S1 is added to a salt container for purification by salt to obtain purified liquid;

[0016] S3. The purification solution from step S2 is added to the purification column and purified by the packing material to obtain the test solution, which can then be used for detection.

[0017] The salt package comprises the following components by weight: 4 parts anhydrous sodium sulfate and 1 part sodium chloride.

[0018] The salt comprises the following components by weight: 1 part sodium citrate, 4 parts anhydrous magnesium sulfate, 1 part sodium chloride, and 0.5 parts disodium hydrogen citrate.

[0019] The filler composition includes 5-50% nano-graphitized carbon black, 5-90% alumina, 5-50% C18 carbon powder, 5-90% silica gel, 5-50% molecularly imprinted polymer, 5-50% aluminosilicate adsorbent, and 5-90% activated carbon.

[0020] The nano-graphitized carbon black is prepared using the following method:

[0021] S4. Take 100g of nano-graphitized carbon black and 500mL of 40% nitric acid, heat the mixture in a reflux reflux apparatus until boiling for 8 hours to obtain a suspension.

[0022] S5. The suspension is allowed to stand at room temperature until the solution separates into layers. The supernatant is then removed to obtain the precipitate. An equal amount of water as the supernatant is added to the precipitate, and the mixture is heated to boiling for 1 hour to obtain the suspension. The suspension is allowed to stand until the solution separates into layers. The precipitate is heated to boiling multiple times to obtain a precipitate and supernatant layer solution after multiple washings.

[0023] S6. The layered solution is washed and separated in a centrifuge until the pH value of the supernatant remains constant; the layered solution is filtered to obtain a precipitate, which is then dried to obtain the nano-graphitized carbon black.

[0024] The silicone is prepared using the following method:

[0025] S7. Gold nanoparticles with a diameter of 10-15 nm were obtained by reducing chloroauric acid with sodium citrate.

[0026] S8. Add 50μm fully porous silica gel to the reactor, then add 30mL xylene, 20mL mercaptosilane reagent, and 15mL pyridine in sequence. Heat under reflux for 24 hours and then cool down. Wash the product with toluene, dichloromethane, methanol, and acetone and then dry it.

[0027] S9. Add the initially prepared gold nanoparticles to another reactor, then add excess n-octadecyl mercaptan, and heat under reflux for 48 hours; filter the product and wash it with methanol and acetone, then dry it to obtain the final product.

[0028] The molecularly imprinted polymer was prepared using the following method:

[0029] S10. The polytoxin to be tested is dissolved in a mixture of chloroform and tetrahydrofuran, wherein the volume ratio of chloroform to tetrahydrofuran is 1:20-20:1; a functional monomer is added, wherein the mass ratio of the functional monomer to the polytoxin to be tested is 1:10-10:1, and the mixture is shaken in a shaker for 4-12 hours to allow the polytoxin to be tested and the functional monomer to fully react and form a stable supramolecular complex.

[0030] S11. Add EGDMA crosslinking agent and AIBN initiator, wherein the mass ratio of EGDMA crosslinking agent to the polytoxin to be tested is 1:20-20:1, and the mass ratio of AIBN initiator to the polytoxin is 1:20-20:1;

[0031] S12. Place the mixed solution into an ampoule, degas it by sonication, purge with nitrogen for 15 minutes to remove oxygen, seal it, and place the ampoule in a constant temperature water bath at 50-80℃ for 12-36 hours to heat and polymerize. The resulting blocky polymer solid is then crushed and passed through a 150-mesh sieve to obtain polymer powder.

[0032] S13. The polymer powder is extracted with a methanol solution containing acetic acid in a Soxhlet extractor for more than 48 hours to remove the template molecules. The eluted polymer is repeatedly washed with distilled water to remove methanol and acetic acid, and then vacuum dried at 50-100℃ to obtain the molecularly imprinted polymer.

[0033] In the methanol solution of acetic acid, the volume ratio of acetic acid is 10%.

[0034] The advantages of this invention are:

[0035] 1. The purification column structure of this invention is highly efficient and fast for purifying fungal toxins, with a purification operation time of no more than 20 minutes, which greatly shortens the pretreatment time for purification.

[0036] 2. This invention can simultaneously purify 77 common fungal toxins, is applicable to food samples with different matrices, has a wide range of applications, and has a good purification effect;

[0037] 3. The packing material used in the purification structure is a common chemical substance, which is stable, easy to manufacture and store, and convenient and quick to use; the packing material is treated before use, which changes the structure of the packing material and makes it highly selective for the purification of fungal toxins;

[0038] 4. The purification column uses a composite of multiple packing materials, which has a better purification effect on the fungal toxins to be tested. Attached Figure Description

[0039] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the purification structure.

[0041] Figures 2(a)-2(d) High-resolution mass spectra of 77 fungal toxin compounds.

[0042] Attached labels: 1-fixed frame, 2-extraction tube, 3-salt bag bottle, 4-purification column. Detailed Implementation

[0043] To facilitate a better understanding of the present invention, the following examples are provided in conjunction with the accompanying drawings. These examples fall within the scope of protection of the present invention, but do not limit the scope of protection of the present invention.

[0044] Example 1

[0045] A purification structure for 77 fungal toxins includes a frame, on which an extraction tube 2, a salt bottle 3, and a purification column 4 are mounted.

[0046] Extraction tube 2 and purification column 4 are respectively located on both sides of the fixing frame 1;

[0047] The salt bottle 3 is placed on the mounting bracket 1 in the area between the extraction tube 2 and the purification column 4;

[0048] Purification column 4 includes a filter column, and a one-way valve is provided at the end of the filter column;

[0049] The extraction tube 2 contains a salt pack, the salt pack bottle 3 contains salt, and the purification column 4 contains packing material.

[0050] A sample purification method involving 77 fungal toxins includes the following steps:

[0051] S1. Weigh a sample containing multiple fungal toxins, add it to an extraction tube, purify it with a salt pack, add an acetonitrile aqueous solution containing formic acid to extract the sample, let it stand and centrifuge, and take the supernatant.

[0052] S2. The supernatant from step S1 is added to a salt container for purification by salt to obtain purified liquid;

[0053] S3. The purification solution from step S2 is added to the purification column and purified by the packing material to obtain the test solution, which can then be used for detection.

[0054] The salt packet contains the following components by weight: 4 parts anhydrous sodium sulfate and 1 part sodium chloride.

[0055] The salt content comprises the following components by weight: 1 part sodium citrate, 4 parts anhydrous magnesium sulfate, 1 part sodium chloride, and 0.5 parts disodium hydrogen citrate.

[0056] The filler composition includes 5-50% nano-graphitized carbon black, 5-90% alumina, 5-50% C18 carbon powder, 5-90% silica gel, 5-50% molecularly imprinted polymer, 5-50% aluminosilicate adsorbent, and 5-90% activated carbon.

[0057] Nano-graphitized carbon black is prepared using the following method:

[0058] S4. Take 100g of nano-graphitized carbon black and 500mL of 40% nitric acid, heat the mixture in a reflux reflux apparatus until boiling for 8 hours to obtain a suspension.

[0059] S5. The suspension is allowed to stand at room temperature until the solution separates into layers. The supernatant is then removed to obtain the precipitate. An equal amount of water as the supernatant is added to the precipitate, and the mixture is heated to boiling for 1 hour to obtain the suspension. The suspension is allowed to stand until the solution separates into layers. The precipitate is heated to boiling multiple times to obtain a precipitate and supernatant layer solution after multiple washings.

[0060] S6. The layered solution is washed and separated in a centrifuge until the pH of the supernatant remains constant; the layered solution is filtered to obtain the precipitate, dried, and nano-graphitized carbon black.

[0061] Silicone is prepared using the following method:

[0062] S7. Gold nanoparticles with a diameter of 10-15 nm were obtained by reducing chloroauric acid with sodium citrate.

[0063] S8. Add 50μm fully porous silica gel to the reactor, then add 30mL xylene, 20mL mercaptosilane reagent, and 15mL pyridine in sequence. Heat under reflux for 24 hours and then cool down. Wash the product with toluene, dichloromethane, methanol, and acetone and then dry it.

[0064] S9. Add the initially prepared gold nanoparticles to another reactor, then add excess n-octadecyl mercaptan, and heat under reflux for 48 hours; filter the product and wash it with methanol and acetone, then dry it to obtain the final product.

[0065] Molecularly imprinted polymers are prepared using the following methods:

[0066] S10. The polytoxin to be tested is dissolved in a mixture of chloroform and tetrahydrofuran, wherein the volume ratio of chloroform to tetrahydrofuran is 1:20-20:1; a functional monomer is added, wherein the mass ratio of the functional monomer to the polytoxin to be tested is 1:10-10:1; the mixture is shaken in a shaker for 4-12 hours to allow the polytoxin to be tested and the functional monomer to fully react and form a stable supramolecular complex.

[0067] S11. Add EGDMA crosslinking agent and AIBN initiator. The mass ratio of EGDMA crosslinking agent to the polytoxin to be tested is 1:20-20:1, and the mass ratio of AIBN initiator to the polytoxin is 1:20-20:1.

[0068] S12. Place the mixed solution into an ampoule, degas it by sonication, purge with nitrogen for 15 minutes to remove oxygen, seal it, and place the ampoule in a constant temperature water bath at 50-80℃ for 12-36 hours to heat and polymerize. The resulting blocky polymer solid is then crushed and passed through a 150-mesh sieve to obtain polymer powder.

[0069] S13. Extract the polymer powder with a methanol solution containing acetic acid in a Soxhlet extractor for more than 48 hours to remove the template molecules. After elution, wash the polymer repeatedly with distilled water to remove methanol and acetic acid, and dry it under vacuum at 50-100℃ to obtain the molecularly imprinted polymer.

[0070] In a methanol solution of acetic acid, the volume ratio of acetic acid is 10%.

[0071] Specifically:

[0072] The salt packet contains 4g of anhydrous sodium sulfate and 1g of sodium chloride.

[0073] The salt composition is as follows: 1g sodium citrate, 4g anhydrous magnesium sulfate, 1g sodium chloride, and 0.5g disodium hydrogen citrate.

[0074] The filler composition is as follows: 2g of nano-graphitized carbon black, 1g of alumina, 0.5g of C18 carbon powder, 0.5g of aluminosilicate adsorbent, 0.5g of silica gel, 0.25g of molecularly imprinted polymer, and 0.25g of activated carbon.

[0075] Comparative Example 1

[0076] The samples were purified using a dispersion solid-phase extraction (QuEChERS) method. Specifically, the homogenized samples were extracted with a 1% acetic acid acetonitrile solution, followed by the addition of anhydrous magnesium sulfate and sodium acetate, followed by shaking, centrifugation, and separation. The upper organic phase was then subjected to dispersion solid-phase extraction, using N-propylethylenediamine (PSA) as an adsorbent to remove fatty acids, pigments, etc. Anhydrous magnesium sulfate was used to remove residual moisture, and an appropriate amount of formate acetate was added to improve the stability of easily alkaline-soluble components in the sample solution.

[0077] test

[0078] Purification and detection of 77 mycotoxins in corn flour.

[0079] Sample: One 2kg bag of corn flour, production date March 2022, shelf life 12 months, place of origin Nanning.

[0080] Instrument: High performance liquid chromatography-tandem mass spectrometry.

[0081] Evaluation criteria: Laboratory quality control standard for food physicochemical testing (GBT 27404-2008), spiked recovery rate ≥60%.

[0082] The types of fungal toxins detected during purification include: aflatoxin B1, G1, B2, G2, vomitoxin, ochratoxin A, T-2 toxin, HT-2 toxin, zearalenone and its derivatives, etc., as detailed in Table 1.

[0083] Table 1. List of names and molecular information of 77 fungal toxins

[0084]

[0085]

[0086] (1) Sample preparation

[0087] Ten portions of corn flour, each weighing 10g, were randomly selected. A mixed standard solution of 77 mycotoxins was prepared as shown in Table 1, with each mycotoxin having a concentration of 10μg / mL. 10mL of the mycotoxin standard solution was added to the corn flour to obtain a corn matrix sample with mixed standard.

[0088] (2) Sample purification

[0089] ① Take 5 samples of corn flour treated by (1) and purify them according to the method in Example 1, specifically as follows:

[0090] Weigh 5.0g of spiked sample into an extraction tube, mix thoroughly with the salt packet, add 20mL of 80% acetonitrile water containing 0.1% (v / v) formic acid, shake and extract for 30min, then extract at 4000r / min, and take the supernatant for purification.

[0091] Add 5 ml of supernatant to the salt flask, mix thoroughly with the salt, and let stand. If necessary, collect the supernatant by centrifugation or filtration through glass fiber filter paper. Use a push-button purification column to draw at least 3 ml of supernatant, attach the one-way valve, and press the push-button to pass the supernatant through the multi-functional purification column. Filter through a 0.22 μm microporous membrane and perform liquid chromatography-mass spectrometry (LC-MS).

[0092] ② Take the remaining 5 samples of corn flour treated in (1) and purify them according to Comparative Example 1.

[0093] (3) Sample testing

[0094] The purified samples were analyzed using high performance liquid chromatography-tandem mass spectrometry to detect the spiked recovery of mycotoxins.

[0095] Chromatographic conditions for high performance liquid chromatography (HPLC): Mobile phase A was an aqueous solution containing 0.5% acetic acid and 2 mM ammonium acetate; mobile phase B was a methanol solution containing 0.5% acetic acid and 2 mM ammonium acetate. Gradient elution was used: 0-2 min: 10% B; 2-14 min: 10% B; 14-15 min: 97% B; 15-15.1 min: 10% B; 15.1-16 min: 10% B; column temperature: 40℃.

[0096] Mass spectrometry conditions: Electrospray ionization (ESI) source was used for scanning in positive ion mode (ESI+) and negative ion mode (ESI-), and multiple reaction monitoring (MRM) was used for monitoring.

[0097] The test results are detailed in Tables 1 and 2.

[0098] Table 2. Linear equation, recovery rate, and limit of quantitation for Example 1

[0099]

[0100]

[0101]

[0102]

[0103] As shown in Table 2, the sample purified using the method of this application in Example 1 had a spiked recovery rate of 63.3-118.2% and a relative standard deviation of less than 5%, which met the requirements for qualitative and quantitative analysis of 77 fungal toxins.

[0104] Table 3 shows the linear equation, correlation coefficient, and linear range for Comparative Example 1.

[0105]

[0106] As shown in Table 3, the QuEChERS purification treatment of Comparative Example 1 only purified 16 toxins, and the recovery rates of five items, namely deoxynivalenol (DON), deoxynivalenol-3-glucoside (DON-3G), 3-acetyldeoxynivalenol (3-ACDON), 15-acetyldeoxynivalenol (15-ACDON), and aflatoxin (ST), were low.

[0107] Therefore, a comparison of the data in Tables 2 and 3 shows that the purification column structure and purification method of this application have a more significant effect on the purification of mycotoxins compared with the QuEChERS method in terms of the types of toxins treated and the spiked recovery rate; the purification column structure and packing materials used in this application have a more significant effect on the purification of mycotoxins.

[0108] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, the phrase "comprising an element defined as..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0109] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A sample purification method involving 77 fungal toxins, characterized in that, The sample is purified using a purification structure, which includes a frame (1) and an extraction tube (2), a salt bottle (3) and a purification column (4) on the frame (1). The extraction tube (2) and the purification column (4) are respectively located on both sides of the fixing frame (1); The salt bottle (3) is located on the mounting bracket (1) in the area between the extraction tube (2) and the purification column (4); The purification column (4) includes a filter column (41), and a one-way valve (42) is provided at the end of the filter column (41); The extraction tube (2) is equipped with a salt pack, the salt pack bottle (3) is equipped with salt, and the purification column (4) is equipped with packing material. The purification treatment method includes the following steps: S1. Weigh a sample containing multiple fungal toxins and add it to an extraction tube (2). After purification with a salt pack, add an acetonitrile aqueous solution containing formic acid for sample extraction. Allow the sample to stand and centrifuge, and take the supernatant. S2. The supernatant from step S1 is added to a salt-filled bottle (3) for salt purification to obtain purified liquid; S3. The purification solution from step S2 is added to the purification column (4) and purified by the packing material to obtain the test solution, which can then be used for detection. The filler composition includes 5-50% nano-graphitized carbon black, 5-90% alumina, 5-50% C18 carbon powder, 5-90% silica gel, 5-50% molecularly imprinted polymer, 5-50% aluminosilicate adsorbent, and 5-90% activated carbon. The nano-graphitized carbon black is prepared using the following method: S4. Take 100g of nano-graphitized carbon black and 500mL of 40% nitric acid, heat the mixture in a reflux reflux apparatus until boiling for 8 hours to obtain a suspension. S5. The suspension is allowed to stand at room temperature until the solution separates into layers. The supernatant is then removed to obtain the precipitate. An equal amount of water as the supernatant is added to the precipitate, and the mixture is heated to boiling for 1 hour to obtain the suspension. The suspension is allowed to stand until the solution separates into layers. The precipitate is heated to boiling multiple times to obtain a precipitate and supernatant layer solution after multiple washings. S6. The layered solution is washed and separated in a centrifuge until the pH value of the supernatant remains constant; the layered solution is filtered to obtain the precipitate, dried, and nano-graphitized carbon black is obtained.

2. The sample purification method involving 77 mycotoxins according to claim 1, characterized in that, The salt package comprises the following components by weight: 4 parts anhydrous sodium sulfate and 1 part sodium chloride.

3. The sample purification method involving 77 mycotoxins according to claim 2, characterized in that, The salt comprises the following components by weight: 1 part sodium citrate, 4 parts anhydrous magnesium sulfate, 1 part sodium chloride, and 0.5 parts disodium hydrogen citrate.

4. A sample purification method involving 77 mycotoxins according to claim 3, characterized in that, The silicone is prepared using the following method: S7. Gold nanoparticles with a diameter of 10-15 nm were obtained by reducing chloroauric acid with sodium citrate. S8. Add 50μm fully porous silica gel to the reactor, then add 30mL xylene, 20mL mercaptosilane reagent, and 15mL pyridine in sequence. Heat under reflux for 24 hours and then cool down. Wash the product with toluene, dichloromethane, methanol, and acetone and then dry it. S9. Add the initially prepared gold nanoparticles to another reactor, then add excess n-octadecyl mercaptan, and heat under reflux for 48 hours; filter the product and wash it with methanol and acetone, then dry it to obtain the final product.

5. A sample purification method involving 77 mycotoxins according to claim 4, characterized in that, The molecularly imprinted polymer was prepared using the following method: S10. The polytoxin to be tested is dissolved in a mixture of chloroform and tetrahydrofuran, wherein the volume ratio of chloroform to tetrahydrofuran is 1:20-20:1; a functional monomer is added, wherein the mass ratio of the functional monomer to the polytoxin to be tested is 1:10-10:1, and the mixture is shaken in a shaker for 4-12 hours to allow the polytoxin to be tested and the functional monomer to fully react and form a stable supramolecular complex. S11. Add EGDMA crosslinking agent and AIBN initiator, wherein the mass ratio of EGDMA crosslinking agent to the polytoxin to be tested is 1:20-20:1, and the mass ratio of AIBN initiator to the polytoxin is 1:20-20:1; S12. Place the mixed solution into an ampoule, degas it by sonication, purge with nitrogen for 15 minutes to remove oxygen, seal it, and place the ampoule in a constant temperature water bath at 50-80℃ for 12-36 hours to heat and polymerize. The resulting blocky polymer solid is then crushed and passed through a 150-mesh sieve to obtain polymer powder. S13. The polymer powder is extracted with a methanol solution containing acetic acid in a Soxhlet extractor for more than 48 hours to remove the template molecules. The eluted polymer is repeatedly washed with distilled water to remove methanol and acetic acid, and then vacuum dried at 50-100℃ to obtain the molecularly imprinted polymer.

6. A sample purification method involving 77 mycotoxins according to claim 5, characterized in that, In the methanol solution of acetic acid, the volume ratio of acetic acid is 10%.

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