Determination of Chloramphenicol in Chicken Muscle by High Performance Liquid Chromatography and UV-Diode Array Detection

Determination of chloramphenicol residues in shrimps by liquid chromatography-mass spectrometry

A liquid chromatographic method with mass spectrometric detection and identification (LC-MS) is presented for the determination of chloramphenicol (CAP) in shrimp tissues. Homogenized shrimp samples were extracted with phosphate buffer (pH 7.0). Clean-up was carried out on a C(18) SPE cartridge. Chloramphenicol was determined by LC-MS-ESI in negative mode. The column used was a Symmetry Shield with a mixture of acetonitrile-water (25:75) as mobile phase. Shrimp samples were fortified at CAP levels between 0.2 and 50 ng g(-1) with 5D-CAP as internal standard. At these levels, accuracies lay between 101 and 110% and between-day reproducibilities were lower than 7.1%, expressed as the variation coefficient of the mean. Limit of decision (CCalpha) was 0.02 ng g(-1). Limit of quantitation (LOQ) was 0.2 ng g(-1).

Analysis of chloramphenicol in honeys of different geographical origin by liquid chromatography coupled to electrospray ionization tandem mass spectrometry

A sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed to detect trace amounts of the antibiotic chloramphenicol (CAP) in honey. The methodology entailed a solid-phase extraction of aqueous honey solutions followed by liquid-liquid partitioning, filtration and direct injection onto the LC-MS/MS system. Honey extracts were spiked with an isotopically labelled internal standard (d(5)-CAP) to compensate for analyte loss and potential ion suppression during the MS stage. Detection of the analyte was achieved by negative ionization electrospray in the selected reaction monitoring (SAM) mode. For confirmation, four characteristic mass transitions were monitored each for the analyte and the surrogate standard. The method was validated according to the latest European Union criteria for the analyses of veterinary drug residues in food. At all three fortification levels studied (0.1, 0.2, 0.5 microg kg(-1)) the method was accurate to within 15%. The repeatability and within-laboratory reproducibilities were <12 and 18%, respectively. The decision limit (CC alpha) and detection capability (CC beta) were both <0.1 microg kg(-1). The procedure provides a sensitive and reliable method for the determination of residues of chloramphenicol in honey. Numerous raw honeys of various geographical origins were analysed, showing extensive contamination particularly those of Chinese origin.