Application of Magnetic Solid Phase Dispersion Extraction Agent in Detecting the Content of Mycotoxins in Wheat

Abstract

This application belongs to the technical field of mycotoxin detection, and specifically relates to the application of a magnetic solid-phase dispersion extractant in detecting the mycotoxin content in wheat. The magnetic solid-phase dispersion extractant is NH2-Fe3O4@TpBD-COF. As a magnetic solid-phase microextraction agent, NH2-Fe3O4@TpBD-COF adopted in the present invention only needs 10 minutes to complete the treatment process in the technical solution provided by the present invention, featuring a short required time; compared with the commonly used solid-phase microextraction column, the technical solution provided by the present invention only requires a usage amount of 10 mg, featuring low cost; compared with the disposable extraction column, NH2-Fe3O4@TpBD-COF adopted in the present invention can be reused 8 times after simple cleaning, featuring environmental friendliness.

Description

Technical Field

[0001] This application belongs to the technical field of mycotoxin detection, and specifically relates to the application of a magnetic solid-phase dispersion extractant in detecting the content of mycotoxins in wheat. Background Art

[0002] Currently, toxicological studies on enniatins and alternariol toxins have shown that they have chronic toxicity, and the pollution range is wide. The synchronous pollution probability in grains such as wheat is high. Among them, 4 enniatins (enniatin A, enniatin A1, enniatin B, enniatin B1) and 3 alternariol toxins (alternariol, alternariol monomethyl ether, tentoxin) are representative. However, there are few current studies on the synchronous detection of these two types of mycotoxins. And the current detection methods are seriously interfered by complex food matrices, making it difficult to specifically enrich these target mycotoxins. Therefore, the development of a method for detecting enniatins and alternariol toxins remains to be explored. Summary of the Invention

[0003] The purpose of the present invention is to solve the deficiencies of the prior art and provide the application of a magnetic solid-phase dispersion extractant in detecting the content of mycotoxins in wheat, specifically adopting the following technical solutions:

[0004] In the first aspect, the present invention provides the application of a magnetic solid-phase dispersion extractant in detecting the content of mycotoxins in wheat, and the magnetic solid-phase dispersion extractant is NH2-Fe3O4@TpBD-COF; the preparation method of the NH2-Fe3O4@TpBD-COF includes the following steps:

[0005] S1. Using FeCl3·6H2O, anhydrous sodium acetate and hexamethylenediamine as raw materials, and ethylene glycol as a solvent, reacting under the condition of 190 °C - 210 °C. After the reaction, wash and perform magnetic separation to obtain nano NH2-Fe3O4;

[0006] S2. Mix the nano NH2-Fe3O4 with a mixed solution of 4-dioxane and n-butanol, then add trimesoylbenzene and benzidine, and use acetic acid as a catalyst to react under the condition of 50 °C - 70 °C, and wash to obtain the NH2-Fe3O4@TpBD-COF.

[0007] For the preparation method of NH2-Fe3O4@TpBD-COF of the present invention, the magnetic separation carrier is nano-amino-functionalized Fe3O4, which can provide a higher specific surface area and amino groups as the in-situ growth points of TpBD-COF, improve the magnetic separation efficiency, and at the same time enhance the stability of NH2-Fe3O4@TpBD-COF to avoid the detachment of TpBD-COF caused by repeated use.

[0008] As a further preferred embodiment, the dosage ratio of FeCl3·6H2O, anhydrous sodium acetate, hexamethylenediamine and ethylene glycol in S1 is 1.0 g: 4.0 g: 3.6 g: 30 mL.

[0009] As a further preferred embodiment, the dosage ratio of nano NH2-Fe3O4, mixed solution, phloroglucinol trimethylformyl and benzidine in S2 is 80 mg: 30 mL: 60 mg: 80 mg; the volume ratio of 4-dioxane and n-butanol in the mixed solution is 4:1.

[0010] As a further preferred embodiment, the wheat mycotoxins include at least one of enniatin A (ENNA), enniatin A1 (ENNA1), enniatin B (ENNB), enniatin B1 (ENNB1), alternariol (AOH), alternariol monomethyl ether (AME), and tentoxin (TEN).

[0011] In a second aspect, the present invention provides a method for detecting wheat mycotoxins, comprising the following steps:

[0012] Mix the sample to be tested with an extraction solvent, extract, centrifuge, dry the supernatant, re-dissolve it, then add the above magnetic solid-phase dispersion extractant for extraction. After the extraction is completed, magnetically separate to remove the supernatant, and add an elution solvent for elution to obtain an eluate;

[0013] Quantitatively detect and analyze the eluate by using an ultra-high performance liquid chromatography-tandem mass spectrometer to obtain the content of wheat mycotoxins.

[0014] As a further preferred embodiment, both the extraction solvent and the elution solvent are a mixed solution of acetonitrile and methanol;

[0015] The volume ratio of the acetonitrile to the methanol is 6:4.

[0016] The above-mentioned ratio provided by the present invention can significantly reduce the matrix effect of the sample. The obtained sample solution for testing has few impurities and low viscosity, can effectively reduce the influence of impurities on qualitative and quantitative analysis, and at the same time reduce the time and cost of the enrichment and purification process of the target mycotoxin.

[0017] As a further preferred embodiment, the dosage ratio of the sample to be tested, the extraction solvent, the magnetic solid-phase dispersion extractant and the elution agent is 1 g: 5 mL: 10 mg: 1 mL.

[0018] As a further preferred embodiment, the adsorption time during the extraction with the above magnetic solid-phase dispersion extractant is 5 min; the elution time of the elution agent is 2 min.

[0019] As a further preferred embodiment, the chromatographic conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry are as follows:

[0020] The aqueous solution of 0.1% formic acid and 5 mM ammonium formate is used as mobile phase A, and acetonitrile is used as mobile phase B;

[0021] The chromatographic column is: C 18 -PFP, 150 mm × 2 mm × 4 µm;;

[0022] The elution conditions are: using the aqueous solution of 0.1% formic acid and 5 mM ammonium formate as mobile phase A. From 0 min to 3 min, 30% A; from 3 min to 3.5 min, 30% A - 0% A; from 3.5 min to 5 min, 0% A; from 5 min to 5.5 min, 0% A - 30% A; from 5.5 min to 10 min, 30% A; the post-run time is 2 min;

[0023] The injection volume is 3.0 µL;

[0024] The flow rate is 0.3 mL / min.

[0025] As a further preferred embodiment, the mass spectrometry conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry are as follows:

[0026] Ionization mode: ESI;

[0027] Detection mode: multiple reaction monitoring mode;

[0028] Nebulizing gas: nitrogen;

[0029] Drying gas temperature: 350 °C;

[0030] Drying gas flow rate: 10 L / min;

[0031] Nebulizer pressure: 40 psi;

[0032] Capillary voltage: 4000 V.

[0033] The beneficial effects of the present invention are as follows:

[0034] (1) The NH2-Fe3O4@TpBD-COF adopted in the present invention is used as a magnetic solid-phase microextraction agent, which only needs 10 min to complete the treatment process in the technical solution provided by the present invention, having the characteristic of short required time; compared with the commonly used solid-phase microextraction column, the technical solution provided by the present invention only needs 10 mg of usage amount, having the characteristic of low cost; compared with the disposable extraction column, the NH2-Fe3O4@TpBD-COF adopted in the present invention can be reused 8 times after simple cleaning, having the characteristic of environmental friendliness.

[0035] (2) The detection method provided by the present invention has good stability, high accuracy and precision, requires low time and cost, can quantitatively detect enniatins and alternariol in wheat at 0.5 μg / kg and above, and the detection limit reaches 0.05 μg / kg - 0.5 μg / kg. Description of the Drawings

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0037] Figure 1 Shown are the total ion chromatograms of 7 mycotoxins before and after treatment with NH2-Fe3O4@TpBD-COF;

[0038] Figure 2 Shown are the extraction results of different extraction solvents;

[0039] Figure 3 Shown are the extraction results of different dosages of the NH2-Fe3O4@TpBD-COF magnetic solid-phase dispersion extractant;

[0040] Figure 4 Shown are the extraction results of different adsorption times of the NH2-Fe3O4@TpBD-COF magnetic solid-phase dispersion extraction;

[0041] Figure 5 Shown are the evaluation results of the number of repeated uses of the NH2-Fe3O4@TpBD-COF magnetic solid-phase dispersion extractant;

[0042] Figure 6 Shown are the comparative evaluation results of the adsorption rates of three magnetic solid-phase dispersion extractants. Detailed Embodiments

[0043] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application.

[0044] The reagents and standards used in the examples and comparative examples of the present invention are as follows:

[0045] Alternariol (AOH, 100 µg / mL), Alternariol monomethyl ether (AME, 100 µg / mL), Tenuazonic acid (TEN, 100 µg / mL), Enniatin A (ENNA, 100 µg / mL), Enniatin A1 (ENNA1, 100 µg / mL), Enniatin B (ENNB, 100 µg / mL), and Enniatin B1 (ENNB1, 100 µg / mL) were obtained from Priblob Co., Ltd. in Singapore. Acetonitrile and methanol were purchased from Merck Co., Ltd. in Germany. Formic acid (FA) and ammonium acetate were purchased from Anpel Co., Ltd. in the United States. Distilled water used as the HPLC mobile phase was purchased from Watson Water Co., Ltd. in China.

[0046] Example 1

[0047] A preparation method of a magnetic solid-phase dispersion extraction agent (NH2-Fe3O4@TpBD-COF) specifically includes the following steps:

[0048] (1) Accurately weigh 1.0 g of FeCl3·6H2O, 4.0 g of anhydrous sodium acetate, and 3.6 g of hexamethylenediamine and place them in a 50 mL round-bottom flask. Add 30 mL of ethylene glycol solution, ultrasonically disperse until a transparent solution is obtained, transfer it to a 50 mL reaction kettle, and react at 200 °C for 6 h. After the reaction is completed, the obtained product is washed three times alternately with ultrapure water and ethanol, separated by a magnet, and the black precipitate is collected to obtain nano-NH2-Fe3O 4,；

[0049] (2) Weigh 80 mg of nano-NH2-Fe3O4 and add it to a round-bottom flask. Add 30 mL of 1,4-dioxane / n-butanol (4 / 1, v / v), ultrasonically mix well, add 60 mg of triformylphloroglucinol (Tp), 80 mg of benzidine (BD), and 2 mL of 6 moL / L acetic acid as a catalyst, ultrasonically mix for 5 min to mix well, and react at 60 °C for 4 h. Subsequently, it is washed three times with methanol by magnetic separation to obtain the product NH2-Fe3O4@TpBD-COF.

[0050] Example 2

[0051] The NH2-Fe3O4@TpBD-COF prepared in Example 1 was used to simultaneously detect 4 enniatins and 3 alternariols in wheat. The specific detection process is as follows:

[0052] In this example, wheat added with 7 mycotoxin standards was used as the test sample. The addition amounts of the mycotoxins were 100 µg / kg for 3 alternariols and 50 µg / kg for 4 enniatins.

[0053] (1) Preparation of the test sample:

[0054] Take 1 g of the ground wheat sample, add 5 mL of acetonitrile:methanol (6:4, v / v), vortex for 5 min, and then centrifuge at 10000 g for 5 min; take 2.5 mL of the supernatant, dry it under nitrogen at 40 °C, and redissolve it in 1 mL of deionized water; then, add 10 mg of NH2-Fe3O4@TpBD-COF, adsorb for 5 min, after the adsorption, separate NH2-Fe3O4@TpBD-COF from the solution with a magnet, and then elute it with 1 mL of acetonitrile:methanol (6:4, v / v) by swirling for 2 min to obtain the eluate;

[0055] (2)UPLC-MS / MS detection

[0056] The chromatographic conditions include:

[0057] Separation of the eluate (analyte) was carried out on a C 18 -PFP (150 mm × 2 mm × 4 µm) column at a column temperature of 30 °C. The mobile phase consisted of an aqueous solution (A) containing 0.1% formic acid and 5 mM ammonium formate and acetonitrile (B). The gradient elution program started from 30% A (0 min), held for 3 min, then decreased to 0% A from 3 min to 3.5 min and held for 1.5 min, then the A phase returned to 30% from 5 min to 5.5 min and was held at 30% A for 4.5 min (the gradient elution conditions are shown in Table 1), and the post-run time was 2 min; the injection volume was 3.0 µL, and the flow rate was 0.3 mL / min;

[0058] The mass spectrometry conditions include:

[0059] An electrospray ionization (ESI) source was used, and data acquisition was performed in the multiple reaction monitoring (MRM) mode. The other acquisition parameters of the mass spectrometer were as follows: nebulizing gas, nitrogen; drying gas temperature, 350 °C; drying gas flow rate, 10 L / min; nebulizer pressure, 40 psi; capillary voltage, 4000 V; the mass spectrometry analysis parameters are shown in Table 2:

[0060] Table 1 Gradient elution table

[0061]

[0062] Table 2 Mass spectrometry analysis parameters

[0063]

[0064] Taking the peak areas of a series of standard working solutions of mycotoxin standards as the ordinate and the concentrations of the standard working solutions as the abscissa, plot the standard working curve, and use the standard curve to quantify the mycotoxins in the sample solution to be tested. Calculate the content of mycotoxins in the sample to be tested according to the formula (the calculated result should deduct the blank value). The results are shown in Table 3 (quantitative results). The formula is as follows:

[0065] X = (C × V) / m

[0066] Wherein, in the formula, X is the content of mycotoxins in the sample to be tested, with the unit of μg / kg;

[0067] C is the concentration of mycotoxins in the sample solution to be tested, with the unit of ng / mL;

[0068] V is the volume of the sample solution to be tested after volume fixation, with the unit of mL;

[0069] m is the weighed amount of the sample to be tested, with the unit of g.

[0070] Table 3 Determination results and standard curve

[0071]

[0072] The total ion chromatograms of the 7 mycotoxins before and after treatment with NH2-Fe3O4@TpBD-COF are as Figure 1 shown, wherein, Figure 1 A in is after the 7 mycotoxins are treated with NH2-Fe3O4@TpBD-COF, Figure 1 B in is the 7 mycotoxins without treatment. It can be seen from the results that NH2-Fe3O4@TpBD-COF realizes low-concentration enrichment while greatly reducing the influence of impurity peaks, and has good enrichment and impurity removal effects.

[0073] Example 3

[0074] Use the NH2-Fe3O4@TpBD-COF prepared in Example 1 to simultaneously detect 4 enniatins and 3 alternariol monomethyl ethers in wheat. The specific detection process is as follows:

[0075] The difference from Example 2 is that fresh wheat and aged wheat collected from the market are used as the samples to be tested, with a total of 33 samples, including 21 fresh wheat samples and 12 aged wheat samples; the other parameters and steps remain unchanged. The quantitative results of the detected mycotoxins are shown in Table 4.

[0076] Table 4 Determination of mycotoxin contamination content

[0077]

[0078] ND: Not detected.

[0079] Example 4

[0080] (1)Detection of linear relationship, detection limit and quantification limit

[0081] Using the peak areas obtained from a series of mixed standard working solutions of 7 mycotoxin standards as the ordinate and the corresponding mass concentrations as the abscissa, a standard working curve was plotted. The concentration was calculated based on the peak areas of each standard at 3 times the signal-to-noise ratio (S / N≥3) to determine the method detection limit (LOD); the concentration was calculated based on the peak areas of each standard at 10 times the signal-to-noise ratio (S / N≥3) to determine the method quantification limit (LOQ). The linear regression equations, linear ranges, correlation coefficients, detection limits, and quantification limit results of each standard are shown in Table 5.

[0082] As shown in Table 5, the standard working curves obtained by the method of the present invention have a good linear relationship, with correlation coefficients all >0.997. The LOD is in the range of 0.02 μg / kg - 0.2 μg / kg, and the LOQ is in the range of 0.05 μg / kg - 0.5 μg / kg.

[0083] Table 5 Results of linear relationship, detection limit and quantification limit

[0084]

[0085] (2)Accuracy and precision detection

[0086] Wheat without detected mycotoxins was used as a negative sample.

[0087] A mixed standard intermediate solution of 7 mycotoxin standards at three different concentration levels of low, medium, and high was added to the negative sample to prepare test samples containing different concentration levels of mycotoxins. They were processed according to step (2) of Example 2, injected into a liquid chromatography - mass spectrometry instrument, and the average recoveries and relative standard deviations (RSD) of different standards were calculated. Each standard solution at each concentration level was subjected to 6 parallel tests, and the results are shown in Table 6.

[0088] As shown in Table 6, the recoveries of the 7 mycotoxins were stable in the range of 81.32% - 109.28%, and the relative standard deviations were in the range of 0.17% - 7.30%, indicating that the detection method of the present invention has good accuracy and precision.

[0089] Table 6 Results of accuracy and precision

[0090]

[0091] (3)Method matrix effect

[0092] Wheat without detected mycotoxins was used as a negative sample.

[0093] Extract the negative sample by the method of step (1) in Example 2 to obtain the extract. Based on the standard curve of the standard product in part (1) of this example, dilute the standard product with the extract of the negative sample to obtain the matrix standard curve. Analyze by the method of step (2) in Example 2. Take the peak areas obtained from the series of mixed standard working solutions of the standards of 7 mycotoxins as the ordinate and the corresponding mass concentrations as the abscissa to plot the standard working curve. Calculate the slope K of the standard curve of the standard product and the matrix standard curve, and calculate the matrix effect. The formula is as follows:

[0094] Matrix effect (ME) = ((K matrix standard curve / K standard product standard curve) - 1) * 100

[0095] The results of the matrix effect are shown in Table 7.

[0096] As shown in Table 7, the matrix effects of the 7 mycotoxins are all < 8.4%, belonging to negligible matrix effects (< 10%), indicating that the detection method of the present invention has a good effect on interfering treatment of food matrixes.

[0097] Table 7 Results of matrix effect

[0098]

[0099] Example 5

[0100] Explore the influence of magnetic solid-phase dispersion extraction conditions on the effect

[0101] (1) Explore the influence of the extraction solvent on the effect

[0102] In order to take into account the extraction effects of multiple mycotoxins, 5 groups of mixtures are set as extraction liquids, namely acetonitrile, methanol, acetonitrile / methanol (8:2, v / v) mixture, acetonitrile - methanol (6:4, v / v) mixture, and acetonitrile - methanol (5:5, v / v) mixture. Replace the extraction liquid in step (1) of Example 2 with the above 5 groups of extraction liquids, and the remaining steps are the same as those in Example 2. Calculate the extraction rate according to the content of the mycotoxins contained in the sample to be measured. The results are as Figure 2 shown. The results show that the acetonitrile - methanol (6:4, v / v) mixture has the best extraction effect.

[0103] (2) Explore the influence of the dosage of magnetic solid-phase dispersion extractant on the effect

[0104] In this example, 2 mg - 15 mg of NH2-Fe3O4@TpBD-COF is set as the dosage comparison of the magnetic solid-phase dispersion extractant. Replace the dosage of the magnetic solid-phase dispersion extractant in step (1) of Example 2 with the above dosage, and the remaining implementation steps are the same as those in Example 2. Calculate the extraction rate according to the measured peak area. The results are as Figure 3As shown, the results indicate that for enniatins, a satisfactory extraction rate (>80%) can be obtained with 6 mg of NH2-Fe3O4@TpBD-COF, while for alternariol monomethyl ether, a usage amount of more than 10 mg of NH2-Fe3O4@TpBD-COF is required. Therefore, 10 mg of the magnetic solid-phase dispersive extraction agent is the optimal dosage for 1 g of the sample to be tested.

[0105] (3) Explore the effect of the adsorption time of magnetic solid-phase dispersive extraction on the result

[0106] The time required for the NH2-Fe3O4@TpBD-COF magnetic solid-phase dispersive extraction agent to complete adsorption was evaluated, and 1 min - 10 min was set as the comparison for the magnetic solid-phase dispersive extraction adsorption time. Replace the magnetic solid-phase dispersive extraction adsorption time in step (1) of Example 2 with the above time, and the remaining implementation steps are the same as those in Example 2. Calculate the extraction rate based on the measured peak area. The results are as Figure 4 shown. The results indicate that after an adsorption time of more than 5 min, the extraction rate tends to be stable. Therefore, 5 min is adopted as the preferred magnetic solid-phase dispersive extraction adsorption time.

[0107] (4) Explore the number of times the magnetic solid-phase dispersive extraction agent can be reused

[0108] The same batch of NH2-Fe3O4@TpBD-COF magnetic solid-phase dispersive extraction agent was used for 10 repeated use experiments. After each single experiment, it was washed twice with the elution solvent and then subjected to the next round of adsorption experiment. Replace the magnetic solid-phase dispersive extraction operation in step (1) of Example 2 with the above operation, and the remaining implementation steps are the same as those in Example 2. Calculate the recovery rate based on the measured peak area. The results are as Figure 5 shown. The results indicate that the magnetic adsorbent synthesized in this study maintains a stable recovery rate during repeated use, and the recovery rate of all target substances can be maintained above 70% during 8 repeated uses. After the 9th use, the recovery rate begins to decline. Therefore, the magnetic solid-phase dispersive extraction agent provided by the present invention can be reused up to 8 times.

[0109] Comparative Example 1

[0110] Different magnetic solid-phase dispersive extraction agents were used to simultaneously detect 4 enniatins and 3 alternariol monomethyl ethers in wheat. The specific detection process is as follows: The detection steps are similar to those in Example 2, and the only difference is that NH2-Fe3O4@TAPT-DHTA-COF and NH2-Fe3O4@TAPT-PA-COF are used to replace NH2-Fe3O4@TpBD-COF as the magnetic solid-phase microextraction agent for the experiment. The obtained results are as Figure 6 shown.

[0111] As the results show, the recoveries of NH2-Fe3O4@TAPT-DHTA-COF and NH2-Fe3O4@TAPT-PA-COF in the synchronous enrichment of 7 mycotoxins are lower than those of NH2-Fe3O4@TpBD-COF and cannot meet the methodological requirements. Therefore, NH2-Fe3O4@TpBD-COF is selected as the preferred magnetic solid-phase microextraction agent for this scheme.

[0112] The embodiments of the present application have been described above in conjunction with the accompanying drawings. Specific examples have been used herein to elaborate on the principles and implementation manners of the present application. The description of the above embodiments is only used to help understand the core idea of the present application. However, the present application is not limited to the above specific implementation manners. The above specific implementation manners are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose of the present application and the scope protected by the claims, and all of them belong to the protection scope of the present application.

Claims

1. Application of a magnetic solid-phase dispersion extraction agent in detecting the content of wheat mycotoxin, characterized in that, The magnetic solid-phase dispersion extractant is NH2-Fe3O4@TpBD-COF; the preparation method of the NH2-Fe3O4@TpBD-COF comprises the following steps: S1. Using FeCl3·6H2O, anhydrous sodium acetate and hexamethylenediamine as raw materials, using ethylene glycol as a solvent, reacting under the condition of 190 °C - 210 °C. After the reaction is completed, wash and perform magnetic separation to obtain nano NH2-Fe3O4; S2. Mix the nano NH2-Fe3O4 with a mixed solution of dioxane and n-butanol, then add phloroglucinol trimethylformyl and benzidine, using acetic acid as a catalyst, reacting under the condition of 50 °C - 70 °C, wash to obtain the NH2-Fe3O4@TpBD-COF; The wheat mycotoxin is at least one of enniatin A, enniatin A1, enniatin B, enniatin B1, alternariol, alternariol monomethyl ether, and tentoxin.

2. The application according to claim 1, characterized in that, In S1, the dosage ratio of FeCl3·6H2O, anhydrous sodium acetate, hexamethylenediamine and ethylene glycol is 1.0 g: 4.0 g: 3.6 g: 30 mL.

3. The application according to claim 1, wherein In S2, the dosage ratio of nano NH2-Fe3O4, the mixed solution, phloroglucinol trimethylformyl and benzidine is 80 mg: 30 mL: 60 mg: 80 mg; the volume ratio of dioxane and n-butanol in the mixed solution is 4:

1.

4. A method for detecting wheat mycotoxins, characterized in that, Comprises the following steps: Mix the sample to be tested with an extraction solvent, extract, centrifuge, take the supernatant and dry it, re-dissolve it, then add the magnetic solid-phase dispersion extractant described in claim 1 for extraction. After the extraction is completed, perform magnetic separation to remove the supernatant, and add an elution solvent for elution to obtain an eluate; Quantitatively detect and analyze the eluate by using an ultra-high performance liquid chromatography-tandem mass spectrometry instrument to obtain the content of wheat mycotoxin; The chromatographic conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry instrument are as follows: Using an aqueous solution containing 0.1% formic acid and 5 mM ammonium formate as mobile phase A, and acetonitrile as mobile phase B; The chromatographic column is: C 18 -PFP, 150 mm × 2 mm × 4 µm; The elution conditions are: at 0 min - 3 min, 30% A; at 3 min - 3.5 min, 30% A - 0% A; at 3.5 min - 5 min, 0% A; at 5 min - 5.5 min, 0% A - 30% A; at 5.5 min - 10 min, 30% A, with a post-run time of 2 min; The injection volume is 3.0 µL; The flow rate is 0.3 mL / min; The mass spectrometry conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry instrument are as follows: Ionization mode: ESI; Detection mode: multiple reaction monitoring mode; Nebulizing gas: nitrogen; Dry gas temperature: 350 °C; Dry gas flow rate: 10 L / min; Nebulizer pressure: 40 psi; Capillary voltage: 4000 V; The wheat mycotoxin is at least one of enniatin A, enniatin A1, enniatin B, enniatin B1, alternariol, alternariol monomethyl ether, and tentoxin.

5. The method according to claim 4, characterized in that Both the extraction solvent and the elution solvent are mixed solutions of acetonitrile and methanol; The volume ratio of the acetonitrile to the methanol is 6:

4.

6. The method according to claim 5, wherein The dosage ratio of the sample to be measured, the extraction solvent, the magnetic solid-phase dispersion extraction agent and the elution solvent is 1 g: 5 mL: 10 mg: 1 mL.

7. The method according to claim 6, characterized in that, The adsorption time during extraction by the magnetic solid-phase dispersion extraction agent is 5 min; the elution time by the elution solvent is 2 min.

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