Detection of organophosphorus pesticides in dairy products by thin layer chromatography

Abstract

The aim of the research was to determine the residual amounts of organophosphorus pesticides in milk, after treatment of the skin of cattle, using the method of thin layer chromatography. The studies were carried out on the basis of the Department of Veterinary and Sanitary Expertise of the St. Petersburg State University of Medicine. The material was milk samples taken 7 days and 14 days and 21 days after treatment of the animals. In parallel, control samples containing pure active substance were applied to chromatographic plates. Results were evaluated under UV light using a UVC-HDi UV cabinet. Based on the results of the studies, the dependence and sensitivity of the method to the detection of pesticides in milk after treatment of animals with diazinon-C was established. The size of the spots of the applied samples on day 7 after treatment was less than on day 14, and on day 21, the substance was not detected in the samples. Thus, this method can establish not only the presence of microconcentrations of substances in the samples, but also the dependence of their number on the size of spots on the chromatographic plate.