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

The electrochemical determination of chloramphenicol (CAP) in food using mi ni- and micro- mercury drop electrodes and differential pulse polarography (DPP) has been elaborated. A phosphate buffer with pH 6.6 was used as the b asic 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 t o the determination of chloramphenicol in actual samples it was necessary t o extract this antibiotic with organic solvents such as methanol, ethanol a nd 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 mea t, milk, eggs and their products ranged in the ng/g d.w. range. For purpose s of comparison and verification of the electrochemical results of CAP dete rmination, chloramphenicol was determined in the same samples, by the immun oenzymatic method ELISA.