Quantification and confirmation of four Fusarium mycotoxins in corn by gas chromatography-mass spectrometry-selected ion monitoring.

A rapid method for the simultaneous determination of T-2 toxin, HT-2 toxin, diacetoxyscirpenol and zearalenone has been developed. Corn samples (10 g) are extracted with methanol, defatted with hexane and subsequently cleaned-up using both reversed-phase (C18) and normal-phase (silica gel) Sep-Pak cartridges. Confirmation of identity is made by gas chromatography-mass spectrometry-selected ion monitoring of three ions characteristic of the trimethylsilyl derivatives of the mycotoxins. Use of deuterated internal standards makes the method quantitatively reliable and increases sensitivity. Confirmation of identity as well as quantitation can be achieved at levels of ca. 20-50 ppb, depending on the mycotoxin. Detection limits (without confirmation of identity) are estimated at 1-20 ppb. Recoveries at the 46-111 ppb level ranged from 80 to 103% with coefficients of variation ranging from 1.6 to 14.2%.