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 C18 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 (CCα) was 0.02 ng g−1. Limit of quantitation (LOQ) was 0.2 ng g−1.