Determination of chloramphenicol (CAP) in food products by differential pulse polarography

The electrochemical determination of chloramphenicol (CAP) in food using mini- and micro- mercury drop electrodes and differential pulse polarography (DPP) has been elaborated. A phosphate buffer with pH 6.6 was used as the basic electrolyte. The analysis was based on a peak at the potential Ep = -0.320 V which showed a clearly linear dependence of the peak current on the concentration of chloramphenicol in the sample under investigation. Prior to the determination of chloramphenicol in actual samples it was necessary to extract this antibiotic with organic solvents such as methanol, ethanol and ethyl acetate. In order to separate CAP in its basic form, various modifications of sample preparation procedures were made for the analysis with the use of selected hydrolytic enzymes. The determined quantities of CAP in the samples of meat, milk, eggs and their products ranged in the ng/g d.w. range. For purposes of comparison and verification of the electrochemical results of CAP determination, chloramphenicol was determined in the same samples, by the immunoenzymatic method ELISA.