Determination of chloramphenicol residues in pork and pig liver by LC-MS/MS

A method of determination of chloramphenicol in pork and pork liver by High Liquid chromatography-Tandem Mass Spectrometry(HPLC-MS/MS) was developed.Samples were extracted with acetonitrile and 4% sodium chloride solution,and precipitation protein at the same time,defatted by hexane,and Ethyl acetate liquidliquid extraction,then concentrated and constanted volume.Samples were detected by LC-MS/MS and isolated with Syncronis C 18 and the liquid phase was acetonitrile and water(40∶60),The electrospray ionization(ESI) mass spectrometry was run in negative ion multiple reaction monitoring mode,taking the chloramphenicol-D5as internal standard.At these experimental conditions,chloramphenicol had a good liner relatively(r=0.999 2) between 1～15ng/mL.recovery rate of samples ranged from 90.0%～110.0%,with LOD of 0.1 μ g/kg,and replicability was RSD3.0%.This method could detect the chloramphenicol residue in pork and pork liver,and with a better precision,higher accuracy,better specificity,and the result was satisfied.