Determination of Chloramphenicol in Milk by a Fluorescence Polarization Immunoassay

A procedure for the determination of the drug chloramphenicol using a fluorescence polarization immunoassay (FPIA) was proposed. The optimum pairs of antibodies and antigens labeled with fluorescein were chosen, and the analytical characteristics of the procedure were determined. A rapid procedure for milk sample preparation with the use of a saturated solution of ammonium sulfate was optimized. The total time of sample preparation and determination of chloramphenicol in milk was no longer than 10 min. The detection limits of chloramphenicol in water and milk were 10 ng/mL and 20 mu g/kg, respectively. The procedure developed for the determination of chloramphenicol was tested in the analysis of model and real milk samples. It was found that some milk samples contained chloramphenicol in concentrations of 38-41 mu g/kg, which are several times higher than the maximum permissible concentration (MPC) ( 10 mu g/kg).