Use of high performance liquid chromatography combined with fluorescence detection for the identification and estimation of aflatoxins and ochratoxin in food

A method has been developed for the separation, identification and estimation of six mycotoxins in foods at the μg kg−1 level. The food is extracted by using aqueous acetonitrile and the extract is then washed with 2,2,4‐trimethylpentane and any mycotoxins re‐extracted into chloroform. The extract is then purified using grooved t.l.c. plates coated with silica gel. After chromatography, any fluorescent bands are removed and examined by h.p.l.c. using a fluorescence detector. The method has been tested using a range of foods including total diet samples. Recoveries at twice the detection limit varied from 40 to 95%.