Simultaneous determination of major type B trichothecenes and deoxynivalenol-3-glucoside in animal feed and raw materials using improved DSPE combined with LC-MS/MS.

A simple and reliable method for simultaneous determination of deoxynivalenol-3-glucoside and major type B trichothecenes (deoxynivalenol, nivalenol, fusarenon X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol and deepoxy-deoxynivalenol) in animal feed and raw materials has been developed and validated in this study. The method was based on an improved dispersive solid-phase extraction (DSPE) followed by analysis using high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). Also, matrix-matched calibration curve (R(2)>0.99) was employed to minimize matrix effects and ensure accurate quantification. The recoveries during sample preparation process (including extraction and clean-up) ranged from 79.03% to 118.39%, with intra-day and inter-day relative standard deviation lower than 20% for all the analytes. The limit of quantification ranged from 5.0 μg/kg for deoxynivalenol to 13.6 μg/kg for fusarenon X. The validated method was successfully applied to the analysis of animal feed and corn. The pilot study showed that 37 out of 41 samples were contaminated with deoxynivalenol-3-glucoside at the levels of 6.0-121.0 μg/kg. Most of the type B trichothecenes were also found with the exception of fusarenon X, at the contaminated levels of 10.0-1,382 μg/kg. To the best of our knowledge, this was the first scientific report on the co-occurrence of masked deoxynivalenol and type B trichothecenes in animal feed and raw materials.