Application and improvement of aflatoxin analysis in foods using a multifunctional column and HPLC

In an earlier report, we developed a rapid, sensitive and clean method consisting of non-chloroform extraction, clean-up on a commercial multifunctional cartridge column and HPLC with fluorescence detection for the analyses of aflatoxins. In this report, we applied this method to analyze aflatoxins in nuts, giant corn, cereals, spice and black teas. The method was effective for macadamia nuts, walnuts, hazelnuts, brazil nuts, giant corn, rice, wheat and buckwheat, and the recoveries of aflatoxins B-1, B-2, G(1) and G(2) spiked in them at the level of 10 ng/g were 85 similar to 106%. However, in the chromatograms of spices and black tea, many background peaks were observed. Therefore, we added a purification step with an affinity column to the clean-up of these samples with the multifunctional cartridge column. After the additional purification, most of the background peaks were gone. The recoveries of aflatoxins B1, B-2 and G1 spiked at the level of 10 ng/g were 71 similar to 112% except for the case of B-2 in white pepper(48%). The recoveries of G(2) were 49 similar to 95%.