High performance liquid chromatographic determination of aflatoxins in animal tissues and products.

A method was developed for the determination of aflatoxins, M1, B1, G1, B2, and G2 in animal tissues, meat, eggs, and dairy products by high performance liquid chromatography (HPLC). Previous extraction procedures were modified to optimize the precision and recovery of the method. HPLC is performed isocratically with a 5 micrometer microparticulate octadecylsilica column and fluorometric detection. The analysis is based on treatment of the purified sample extract or standard with trifluoroacetic acid (TFA) to catalyze the hydration of aflatoxins M1, B1, and G1 to the highly fluorescent M2a, B2a, and G2a derivatives. Analysis by HPLC with and without TFA treatment of the extract provides quantitative and qualitative data. The recovery of added aflatoxins and the precision of the recovery depend on the type of sample; mean coefficient of variation for all recovery values was 19.7 +/- 11.0% for the analysis of liver, ground beef, dairy products, and eggs. The method was sensitive, with a detection limit of 0.05 + 0.10 ng/g for each aflatoxin. This procedure provides an alternative to existing thin layer chromatographic methods for determining aflatoxins in animal tissues and products