ABSTRACT

The aim of this study was to perform a optimized method for determination of aflatoxin M₁ in milk. The manner of extraction and clean-up of milk extracts as well conditions of reaction of aflatoxin Mi with TFA and HPLC was described. The main steps of optimized method were: extraction of samples with chloroform, clean-up of extracts on SPE C₁₈ columns and by means of extraction with n-hexane, derivatisation of aflatoxin M₁ with TFA (60°C, 6 minutes) to acetal form - aflatoxin М_2a and determination of aflatoxin by means of the RP-HPLC technique. The mobile phase was a mixture of methanol, isopropanol and water (18+7+75). Fluorometric detection was made at 370/418-700 nm. The mean recovery of aflatoxin M₁ dependent on fortification level was 62-67%, limit of detection was 0,01 µg/1 of milk.