Deoxynivalenol in winter wheat: thin layer chromatographic method and survey

A rapid method for the determination of deoxynivalenol (DON) in wheat was used to analyze 57 wheat samples collected from 4 midwestern states where the winter wheat crop was contaminated with Fusaria. The method involves sample extraction with acetonitrile-water (84 + 16), cleanup by charcoal-alumina column chromatography, and determination by thin layer chromatography (TLC), using an AlCl3 solution spray and heat to form a fluorescent derivative. Recoveries of DON added to wheat at levels as low as 0.2 micrograms/g averaged greater than 80%. DON was detected at an average level of 3.6 micrograms/g; the levels ranged from 0.2 to 9.0 micrograms/g in 54 of 57 of the wheat samples. The quantity of DON was, in general, proportional to the percentage of total damaged kernels (grade). The chemical identity of DON was confirmed by mass spectrometry after isolation with preparative TLC.