Gas-liquid chromatographic determination of T-2 toxin and diacetoxyscirpenol in corn and mixed feeds.

A gas-liquid chromatographic method has been developed for the simultaneous determination of the T-2 toxin and diacetoxyscirpenol (DAS) in corn and mixed feeds. The analytes are extracted with aqueous methanol. Ammonium sulfate is used to denature and precipitate proteinaceous compounds and to salt out low polar compounds. The analytes are selectively concentrated into chloroform, which is washed with aqueous potassium hydroxide to remove acidic compounds. Residual interferences are removed by silica gel column chromatography. Heptafluorobutrylimidazole (HFBI) is added to form esters of the analytes. The HFB-esters are separated on an SE-30 glass column and measured witha 63Ni electron capture detector, using methoxychlor as an internal standard. The method has been applied to corn, livestock feeds, and pet food. The limit of detection is 100 ng T-2 toxin and 25 ng DAS/G. Average recoveries of 105 and 97% and coefficients of variation of 17 and 10% were obtained for T-2 toxin and DAS, respectively.