Rapid thin layer chromatographic determination of aflatoxin M1 in powdered milk

A method has been developed for the detection of aflatoxin M1 in milk. The toxin is extracted with chloroform, the extract is evaporated, and the residue is partitioned between carbon tetrachloride and an aqueous saline-methanol solution. The toxin is once again extracted with chloroform from the methanol solution and analyzed by thin layer chromatography. The limit of detection of M1 in powdered milk is 0.5 microgram/kg; recoveries of added M1 are about 83%. The limit of detection can be improved to 0.3 microgram/kg if the plate is sprayed with an aqueous solution of H2SO4 after development.