DETERMINATION OF DEOXYNIVALENOL IN WHEAT, BARLEY, AND MALT BY COLUMN CLEANUP AND GAS-CHROMATOGRAPHY WITH ELECTRON-CAPTURE DETECTION

A rapid and reliable method to determine deoxynivalenol (DON) in wheat , barley, and malt is described. Samples are extracted with acetonitri le-water (84 + 16). Extracts are eluted through a C-18-alumina (1 + 3) column, evaporated to dryness, and derivatized with trimethylsilylimi dazole-trimethylchlorosilane (100 + 1). DON is identified and quantita ted by capillary gas chromatography with electron capture defection. T his method can quantitate DON levels from 0.2 to 40 ppm, Multiple anal yses of wheat spiked at 2 ppm and of naturally contaminated wheat, mal t, and barley resulted in coefficients of variation of 5.1, 5.1, 6.0, and 9.8%, respectively. Recoveries of DON spikes at 3 levels were 94-1 00% for wheat, 100-105% for barley, and 100-105% for malt. Results for wheat sample analyzed with this procedure (1.9 +/- 0.1 ppm DON) compa red well with results for the same sample analyzed by enzyme-linked im munosorbent assay (1.9 ppm DON) and by liquid chromatography (1.7 ppm DON).