Application of magnetic solid-phase dispersion extractant in detection of content of wheat mycotoxin

Abstract

The invention belongs to the technical field of mycotoxin detection, and particularly relates to application of a magnetic solid-phase dispersion extraction agent to detection of the content of wheat mycotoxin. And the magnetic solid phase dispersion extraction agent is NH2-Fe3O4 (at) TpBD-COF. The preparation method is characterized in that the magnetic solid phase dispersion extraction The NH2-Fe3O4 (at) TpBD-COF adopted by the invention is used as a magnetic solid-phase micro-extraction agent, and the treatment process can be completed in only 10 minutes in the technical scheme provided by the invention, so that the method has the characteristic of short required time; compared with a common solid-phase microextraction column, the technical scheme provided by the invention only needs 10 mg of the solid-phase microextraction column, and has the characteristic of low cost; compared with a disposable extraction column, the NH2-Fe3O4 (at) TpBD-COF adopted by the invention can be repeatedly used for 8 times after being simply cleaned, and has the characteristics of being green and environment-friendly.

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] Current toxicological studies on enniatins and alternariolines have shown that they have chronic toxicity, and the pollution range is extensive. 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 alternariolines (alternariol, alternariol monomethyl ether, tenuazonic acid) 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, and it is difficult to specifically enrich these target mycotoxins. Therefore, the development of a method for detecting enniatins and alternariolines 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. The specific technical solutions are as follows: 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. The magnetic solid-phase dispersion extractant is NH 2 -Fe 3 O 4 @TpBD-COF; The preparation method of the NH 2 -Fe 3 O 4 @TpBD-COF includes the following steps: S1. Using FeCl 3 ·6H 2 O, 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, wash and perform magnetic separation to obtain nano-NH 2 -Fe 3 O 4 ; S2. Mix the nano-NH 2 -Fe 3 O 4 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. Wash to obtain the NH 2 -Fe 3 O 4 @TpBD-COF.

[0004] NH of the present invention 2 -Fe 3 O 4 @TpBD-COF preparation method, the magnetic separation carrier is nano-amino-functionalized Fe 3 O 4 , 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 NH 2 -Fe 3 O 4 @TpBD-COF and avoid the detachment of TpBD-COF caused by repeated use.

[0005] As a further preferred embodiment, in S1, the dosage ratio of FeCl 3 ·6H 2 O, sodium acetate anhydrous, hexamethylenediamine and ethylene glycol is 1.0 g: 4.0 g: 3.6 g: 30 mL.

[0006] As a further preferred embodiment, in S2, the dosage ratio of nano-NH 2 -Fe 3 O 4 , the mixed solution, phloroglucinol trimethylformyl and benzidine is 80 mg: 30 mL: 60 mg: 80 mg; the volume ratio of 1,4-dioxane and n-butanol in the mixed solution is 4:1.

[0007] As a further preferred embodiment, the wheat mycotoxins include at least one of enniatin A (ENNA), enniatin A 1 (ENNA 1 ), enniatin B (ENNB), enniatin B 1 (ENNB 1 ), alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN).

[0008] Second aspect, the present invention provides a method for detecting wheat mycotoxins, comprising the following steps: Mix the sample to be tested with an extraction solvent, extract, centrifuge, dry the supernatant, redissolve, and then add the above magnetic solid-phase dispersion extraction agent for extraction. After the extraction is completed, magnetically separate to remove the supernatant, and add an elution solvent for elution to obtain an eluate; Quantitatively detect and analyze the eluate by an ultra-high performance liquid chromatography-tandem mass spectrometer to obtain the content of wheat mycotoxins.

[0009] As a further preferred embodiment, both the extraction solvent and the elution solvent are a mixed solution of acetonitrile and methanol; The volume ratio of the acetonitrile to the methanol is 6:4.

[0010] The above-mentioned ratio provided by the present invention can significantly reduce the matrix effect of the sample, and the obtained test solution has few impurities and low viscosity, which 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.

[0011] As a further preferred embodiment, the dosage ratio of the test sample, the extraction solvent, the magnetic solid-phase dispersion extractant and the eluent is 1 g:5 mL:10 mg:1 mL.

[0012] As a further preferred embodiment, the adsorption time of the above magnetic solid-phase dispersion extractant during extraction is 5 min; the elution time of the eluent is 2 min.

[0013] As a further preferred embodiment, the chromatographic conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry are as follows: An 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; The chromatographic column is: C 18 -PFP, 150 mm × 2 mm × 4 µm; The elution conditions are: an aqueous solution containing 0.1% formic acid and 5 mM ammonium formate is used 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; The injection volume is 3.0 µL; The flow rate is 0.3 mL / min.

[0014] As a further preferred embodiment, the mass spectrometry conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry 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.

[0015] The beneficial effects of the present invention are: (1) NH adopted by the present invention 2 -Fe3 O 4 @TpBD-COF, as a magnetic solid-phase microextraction agent, only takes 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, the NH 2 -Fe 3 O 4 @TpBD-COF can be reused 8 times after simple cleaning, featuring environmental friendliness.

[0016] (2) The detection method provided by the present invention has good stability, high accuracy and precision, low required time and cost, and can quantitatively detect enniatins and alternariol above 0.5 μg / kg in wheat, with the detection limit reaching 0.05 μg / kg - 0.5 μg / kg. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 Shown are the total ion current chromatograms of 7 mycotoxins before and after treatment with NH 2 -Fe 3 O 4 @TpBD-COF; Figure 2 Shown are the extraction results of different extraction solvents; Figure 3 Shown are the extraction results of different dosages of the NH 2 -Fe 3 O 4 @TpBD-COF magnetic solid-phase dispersion extraction agent; Figure 4 Shown are the extraction results of different adsorption times of the NH 2 -Fe 3 O 4 @TpBD-COF magnetic solid-phase dispersion extraction; Figure 5 Shown are the evaluation results of the number of reuse times of the NH 2 -Fe 3 O 4 @TpBD-COF magnetic solid-phase dispersion extraction agent; Figure 6The figure shows the comparative evaluation results of the adsorption rates of three magnetic solid-phase dispersion extraction agents. Detailed implementation mode

[0019] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying 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 the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0020] The reagents and standards used in the examples and comparative examples of the present invention are as follows: Alternariol (AOH, 100 µg / mL), Alternariol monomethyl ether (AME, 100 µg / mL), T-2 toxin (TEN, 100 µg / mL), Enniatin A (ENNA, 100 µg / mL), Enniatin A 1 (ENNA 1 , 100 µg / mL), Enniatin B (ENNB, 100 µg / mL), Enniatin B 1 (ENNB 1 , 100 µg / mL) were obtained from Priblob Company in Singapore. Acetonitrile and methanol were purchased from Merck Company in Germany. Formic acid (FA) and ammonium acetate were purchased from Anpel Company in the United States. Distilled water used as the HPLC mobile phase was purchased from Watson Water Co., Ltd. in China.

[0021] Example 1 A preparation method of a magnetic solid-phase dispersion extraction agent (NH 2 -Fe 3 O 4 @TpBD-COF) specifically includes the following steps: (1) Accurately weigh 1.0 g of FeCl 3 ·6H 2 O, 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 to a transparent solution, transfer to a 50 mL reaction kettle, and react at 200 °C for 6 h. After the reaction, 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-NH 2 -Fe 3 O 4,； (2) Weigh 80 mg of nano-NH 2 -Fe 3 O 4Add to a round-bottom flask, add 30 mL of 1,4-dioxane / n-butanol (4 / 1, v / v), mix well by ultrasonic, add 60 mg of triformylphloroglucinol (Tp), 80 mg of benzidine (BD), and 2 mL of 6 moL / L acetic acid as a catalyst, ultrasonic for 5 min to mix well, react at 60 °C for 4 h, and then wash three times with methanol by magnetic separation to obtain the product NH 2 -Fe 3 O 4 @TpBD-COF.

[0022] Example 2 Use the NH 2 -Fe 3 O 4 @TpBD-COF prepared in Example 1 for the simultaneous detection of 4 enniatins and 3 alternariol monomethyl ethers in wheat. The specific detection process is as follows: In this example, wheat added with 7 mycotoxin standards was used as the test sample. The addition amounts of mycotoxins were 100 μg / kg for 3 alternariol monomethyl ethers and 50 μg / kg for 4 enniatins.

[0023] (1) Preparation of the test sample: Take 1 g of the pulverized 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 and dry it under nitrogen at 40 °C, and redissolve it in 1 mL of deionized water; then, add 10 mg of NH 2 -Fe 3 O 4 @TpBD-COF, adsorb for 5 min, and after the adsorption is completed, separate NH 2 -Fe 3 O 4 @TpBD-COF from the solution with a magnet, and then elute with 1 mL of acetonitrile:methanol (6:4, v / v) by swirling for 2 min to obtain the eluate; (2) UPLC-MS / MS detection The chromatographic conditions include: Separation of the eluate (analyte) was performed on a C 18Performed on a -PFP (150 mm × 2 mm × 4 µm) column at a column temperature of 30 °C. The mobile phase consisted of an aqueous solution containing 0.1% formic acid and 5 mM ammonium formate (A) 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, phase A returned to 30% from 5 min to 5.5 min and was held at 30% A for 4.5 min (gradient elution conditions are shown in Table 1). The post-run time was 2 min; the injection volume was 3.0 µL, and the flow rate was 0.3 mL / min; The mass spectrometry conditions included: 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: Table 1 Gradient elution table Table 2 Mass spectrometry analysis parameters Using the peak areas of the series of standard working solutions of mycotoxin standards as the ordinate and the concentrations of the standard working solutions as the abscissa, a standard working curve was plotted. The mycotoxins in the sample solution to be measured were quantified using the standard curve, and the content of mycotoxins in the sample to be measured was calculated according to the formula (the blank value should be deducted from the calculation result). The results are shown in Table 3 (quantification results). The formula is as follows: X = (C × V) / m Where, in the formula, X is the content of mycotoxins in the sample to be measured, with the unit of μg / kg; C is the concentration of mycotoxins in the sample solution to be measured, with the unit of ng / mL; V is the volume of the sample solution to be measured after constant volume, with the unit of mL; m is the weighed amount of the sample to be measured, with the unit of g.

[0024] Table 3 Determination results and standard curve The total ion current chromatograms of the untreated and NH 2 -Fe 3 O 4 @TpBD-COF-treated 7 mycotoxins are shown as Figure 1 shown, where Figure 1 A in 2 -Fe 3 O4 After treatment with @TpBD-COF, Figure 1 B in 2 -Fe 3 O 4 @TpBD-COF achieves low-concentration enrichment while significantly reducing the influence of impurity peaks, and has good enrichment and impurity removal effects.

[0025] Example 3 Using the NH 2 -Fe 3 O 4 @TpBD-COF was used to simultaneously detect 4 enniatins and 3 alternariol monomethyl ethers in wheat. The specific detection process is as follows: It is different from Example 2 in that fresh wheat and stored wheat collected from the market were used as the samples to be tested, with a total of 33 samples, including 21 fresh wheat samples and 12 stored wheat samples; the remaining parameters and steps remained unchanged. The quantitative results of the mycotoxins detected are shown in Table 4.

[0026] Table 4 Determination of mycotoxin contamination content ND: Not detected.

[0027] Example 4 (1) Detection of linear relationship, detection limit and quantification limit Taking the peak areas obtained from the 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.

[0028] 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.

[0029] Table 5 Results of linear relationship, detection limit and quantification limit (2) Detection of accuracy and precision Taking wheat without detected mycotoxins as the negative sample.

[0030] To the negative samples, intermediate mixed standard solutions of 7 mycotoxin standards at three different concentration levels of low, medium, and high were added respectively to prepare test samples containing mycotoxins at different concentration levels. They were processed according to the steps (2) of Example 2, injected into a liquid chromatography - mass spectrometry instrument, and the average recovery rates 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.

[0031] As shown in Table 6, the recovery rates 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.

[0032] Table 6 Results of accuracy and precision (3) Matrix effect of the method Wheat without detected mycotoxins was used as a negative sample.

[0033] The negative sample was extracted by the method in step (1) of Example 2 to obtain an extract. Based on the standard curve of the standard in part (1) of this example, the standard was diluted with the extract of the negative sample to obtain a matrix standard curve, and analyzed by the method in step (2) of Example 2. Taking the peak areas obtained from the series of mixed standard working solutions of the 7 mycotoxin standards as the ordinate and the corresponding mass concentrations as the abscissa, a standard working curve was plotted. Calculate the slope K of the standard curve of the standard and the matrix standard curve, and calculate the matrix effect. The formula is as follows: Matrix effect (ME) = ((K matrix standard curve / K standard curve of standard) - 1) * 100 The results of the matrix effect are shown in Table 7.

[0034] As shown in Table 7, the matrix effects of the 7 mycotoxins were 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.

[0035] Table 7 Results of matrix effect Example 5 Explore the influence of magnetic solid phase dispersion extraction conditions on the effect (1) Explore the influence of the extraction solvent on the effect To balance the extraction effects of multiple mycotoxins, 5 groups of mixed solutions were set as extraction solutions, namely acetonitrile, methanol, acetonitrile / methanol (8:2, v / v) mixed solution, acetonitrile-methanol (6:4, v / v) mixed solution, and acetonitrile-methanol (5:5, v / v) mixed solution. Replace the extraction solutions in step (1) of Example 2 with the above 5 groups of extraction solutions, and keep the remaining steps the same as those in Example 2. Calculate the extraction rate according to the mycotoxin content in the sample to be tested. The results are as Figure 2 shown, and the results show that the acetonitrile-methanol (6:4, v / v) mixed solution has the best extraction effect.

[0036] (2) Explore the influence of the dosage of magnetic solid-phase dispersion extractant on the effect In this example, 2 mg - 15 mg of NH 2 -Fe 3 O 4 @TpBD-COF was 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 keep the remaining implementation steps the same as those in Example 2. Calculate the extraction rate according to the measured peak area. The results are as Figure 3 shown, and the results show that for enniatin, 6 mg of NH 2 -Fe 3 O 4 @TpBD-COF can obtain a satisfactory extraction rate (>80%). For alternariol, a dosage of more than 10 mg of NH 2 -Fe 3 O 4 @TpBD-COF is required. Therefore, 10 mg of the magnetic solid-phase dispersion extractant is the optimal dosage for 1 g of the sample to be tested.

[0037] (3) Explore the influence of the magnetic solid-phase dispersion extraction adsorption time on the effect The time required for NH 2 -Fe 3 O 4 @TpBD-COF magnetic solid-phase dispersion extractant to complete adsorption was evaluated, and 1 min - 10 min was set as the comparison of the magnetic solid-phase dispersion extraction adsorption time. Replace the magnetic solid-phase dispersion extraction adsorption time in step (1) of Example 2 with the above time, and keep the remaining implementation steps the same as those in Example 2. Calculate the extraction rate according to the measured peak area. The results are as Figure 4 shown, and the results show that after the 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 dispersion extraction adsorption time.

[0038] (4) Explore the number of times the magnetic solid-phase dispersion extractant can be reused The same batch of NH 2-Fe 3 O 4 The @TpBD-COF magnetic solid-phase dispersion extraction agent was subjected to 10 repeated use experiments. After each single experiment, it was washed twice with an elution solvent and then used for the next round of adsorption experiments. The above operation was used to replace the magnetic solid-phase dispersion extraction operation in step (1) of Example 2, and the remaining implementation steps were the same as those in Example 2. The recovery rate was calculated based on the measured peak area. The results are as Figure 5 shown. The results indicate that the magnetic adsorbent synthesized in this study maintained a stable recovery rate during repeated use, and the recovery rate of all target substances remained above 70% during 8 repeated uses. After the 9th use, the recovery rate began to decline. Therefore, the magnetic solid-phase dispersion extraction agent provided by the present invention can be repeatedly used up to 8 times.

[0039] Comparative Example 1 Different magnetic solid-phase dispersion extraction agents were used for the simultaneous detection of 4 enniatins and 3 alternariol monomethyl ethers in wheat. The specific detection process was as follows: The detection steps were similar to those in Example 2, and the only difference was that NH 2 -Fe 3 O 4 @TAPT-DHTA-COF and NH 2 -Fe 3 O 4 @TAPT-PA-COF were used to replace NH 2 -Fe 3 O 4 @TpBD-COF as the magnetic solid-phase microextraction agent for the experiment. The obtained results are as Figure 6 shown.

[0040] As shown in the results, the recovery rates of NH 2 -Fe 3 O 4 @TAPT-DHTA-COF and NH 2 -Fe 3 O 4 @TAPT-PA-COF in the simultaneous enrichment of 7 mycotoxins were lower than those of NH 2 -Fe 3 O 4 @TpBD-COF and could not meet the methodological requirements. Therefore, NH 2 -Fe 3 O 4 @TpBD-COF was selected as the preferred magnetic solid-phase microextraction agent for this scheme.

[0041] 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 fall within the protection scope of the present application.

Claims

1. Application of a magnetic solid phase dispersion extractant in detecting the mycotoxin content in wheat, characterized in that: The magnetic solid phase dispersed extractant is NH2-Fe3O4@TpBD-COF; the preparation method of NH2-Fe3O4@TpBD-COF comprises the following steps: S1, using FeCl3·6H2O, anhydrous sodium acetate and hexamethylenediamine as raw materials and ethylene glycol as solvent, reacting at 190 ℃-210 ℃, washing and magnetic separation after the reaction to obtain nano NH2-Fe3O4; S2. Mix the nano NH2-Fe3O4 with a mixed solution of 4-dioxane and n-butanol, then add triformylphloroglucinol and benzidine, use acetic acid as a catalyst, react at 50°C-70°C, wash, and obtain the NH2-Fe3O4@TpBD-COF.

2. The use according to claim 1, characterized in that: 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.

3. The use according to claim 1, characterized in that: The dosage ratio of nano-NH2-Fe3O4, mixed solution, triformylphloroglucinol 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.

4. The use according to claim 3, characterized in that: The wheat fungal toxins include at least one of enfusin A, enfusin A1, enfusin B, enfusin B1, alternating spores, alternating spore monomethyl ether, and tengtoxin.

5. A method for detecting wheat mycotoxins, characterized in that: The following steps are involved: The sample to be tested is mixed with an extraction solvent, extracted, centrifuged, the supernatant is blown dry, redissolved, and then the magnetic solid phase dispersion extractant according to claim 1 is added for extraction. After the extraction is completed, the supernatant is removed by magnetic separation, and an elution solvent is added for elution to obtain an eluate; The eluate is subjected to quantitative detection and analysis using ultra-high performance liquid chromatography-tandem mass spectrometry to obtain the content of wheat mycotoxins.

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

4.

7. The method according to claim 6, characterized in that The dosage ratio of the sample to be tested, the extraction solvent, the magnetic solid phase dispersion extractant and the eluent is 1 g: 5 mL: 10 mg: 1 mL.

8. The method according to claim 7, characterized in that The adsorption time of the magnetic solid phase dispersion extractant during extraction is 5 min; the elution time of the eluent is 2 min.

9. The method according to claim 5, characterized in that The chromatographic conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry are as follows: An aqueous solution containing 0.1% formic acid and 5 mM ammonium formate was used as mobile phase A, and acetonitrile was used as mobile phase B; Chromatographic column: C 18 -PFP, 150mm×2mm×4µm; The elution conditions were as follows: 30% A from 0 min to 3 min; 30% A-0% A from 3 min to 3.5 min; 0% A from 3.5 min to 5 min; 0% A-30% A from 5 min to 5.5 min; 30% A from 5.5 min to 10 min, with a post-run time of 2 min; The injection volume was 3.0 µL; The flow rate was 0.3 mL / min.

10. The method according to claim 5, characterized in that The mass spectrometry conditions of the ultra-high performance liquid chromatography-tandem mass spectrometry are as follows: Ionization mode: ESI; Detection mode: multiple reaction monitoring mode; Atomizing gas: nitrogen; Drying gas temperature: 350 ℃; Drying gas flow rate: 10 L / min; Atomizer pressure: 40 psi; Capillary voltage: 4000 V.

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