Determination of Mycotoxins in Wheat Grain by LC-MS/MS using Modified QuEChERS Sample Preparation

The procedure of the mycotoxins determination in wheat grain was developed by LC-MS/MS using modified QuEChERS sample preparation. The method of simultaneous determination of six mycotoxins (aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, T-2 toxin and zearalenone) in wheat grain was validated according to the following criteria: specificity, linearity, limits of detection (LOD), limits of quantification (LOQ), accuracy, and precision. The chromatographic and mass spectrometric conditions for separation and determination of the mycotoxins were optimized during the study. It was established that the most optimal mobile phase for the separation of six mycotoxins is 5 mМ ammonium formate solution in methanol : water : formic acid (5 : 94.9 : 0.1 by volume, eluent A and 95:4.9:0.1 by volume, eluent B). It was found that the correlation coefficients for six mycotoxins range from 0.9990 to 0.9998 (R2 > 0.995). Limits of detection (LOD) and limits of quantification (LOQ) of the mycotoxins are below the maximum permitted levels set by the European Union (EU). Percent recovery in the range from 88 to 103 % indicates the acceptability of the mycotoxin extraction procedure. The relative standard deviation (RSD, %) of the measurement results under conditions of repeatability ranged from 1.94 to 8.76 %. The obtained data suitability evaluation of method (validation) corresponds to criteria European Commission Regulation (EC) No. 401/2006. The validation results showed that LC-MS/MS method with using of modified QuEChERS sample preparation is effective and suitable for the simultaneous quantitation of mycotoxins in wheat grain.