Multifunctional column coupled with liquid chromatography for determination of aflatoxins B1, B2, G1, and G2 in corn,...

An AOAC/IUPAC collaborative study was conducted to evaluate the effectiveness of a multifunctional column for the determination of aflatoxins. The test portion is extracted with acetonitrile-water (9 + 1), the extract is filtered, and the filtrate is passed through the column. The aflatoxins in the eluate are determined by reversed-phase liquid chromatography after derivatization with trifluoroacetic acid. Naturally contaminated corn, almonds, Brazil nuts, peanuts, and pistachio nuts spiked with total aflatoxins at 5, 10, 20, and 30 ng/g were sent to 12 collaborators in the United States, Denmark, France, Japan, and Switzerland. Eleven collaborators completed the study. Average recoveries of total aflatoxins for each spike level for the various commodities (excluding Brazil nuts at 5 ng/g) were 93, 97, 95, and 95%, respectively; the repeatability relative standard deviation (RSDr) ranged from 6.0 to 23.2% and the reproducibility relative standard deviation (RSDR) ranged from 12.0 to 69.4%. The multifunctional column coupled with a liquid chromatographic method for determination of aflatoxins in corn, almonds, Brazil nuts, peanuts, and pistachio nuts has been adopted first action by AOAC INTERNATIONAL.