Determination of ochratoxin A in bile of swine by high-performance liquid chromatography.

A method for the determination of low concentrations of the mycotoxin ochratoxin A (OA) in bile of pigs is described. OA was extracted with acidified chloroform and the extract was purified on a silicagel cartridge, followed by liquid-liquid partition. OA was determined by high-performance liquid chromatography with fluorescence detection. The detection limit was 0.3 ng/ml, the mean recovery was 84%. An enzyme-linked immunosorbent assay proved to be suitable for confirmation of positive results. Because of the low detection limit, biliary elimination of OA in pigs fed with low-contaminated feedstuffs can be examined by this method. This is an important requirement for the study of pharmacokinetic profiles of OA.