[Radioimmunologic determination of the mycotoxin ochratoxin A--a new diagnostic method in Czechoslovakia].

A new radioimmunological method was developed for the determination of the mycotoxin ochratoxin A. The specific antibodies used in this method had been prepared by the immunization of rabbits by means of administration of ochratoxin A conjugate with bovine serum albumin. Their effective affinity constant was Ka = 5.1 X 10(-9) l. Mol-1. The substance used as radioligand was 125I-ochratoxin with a high specific radioactivity (Czechoslovak patent PV 6136, 1986). The average sensitivity of determination (ED 85%) was 10 to 15 picograms per 0.1 ml of sample. The range of the calibration curve was mostly from 5 to 360 picograms.