DETERMINATION OF CHLORAMPHENICOL RESIDUES BY REVERSE-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY IN FOIES GRAS

A reverse phase liquid chromatographic (LC) method for the determinati on of chloramphenicol (CAP) residues in foies gras was tested. The met hod was based on acetonitrile-sodium chloride extraction, sample clean -up with hexane and purification on a Sep-Pak C18 cartridge. Acceptabl e chromatographic separation was obtained for thawed samples with two sample clean-up steps with hexane, a purification step with acetonitri le + water (87.5 + 12.5) (v/v) before the elution of CAP residues by a mixture of acetonitrile + water (70 + 30) (v/v) with a chromatographi c separation on Spherisorb ODS-2 (5 mu m) column using sodium acetate buffer (pH 4.3) + acetonitrile (78 +/- 22) (v/v) as mobile phase. The detection limit of the method was 2.5 mu g/kg. The mean recovery from spiked samples at the 10 mu g/kg level was 55.7 +/- 8.7%.