Determination of trichlorfon and dichlorvos residues in aquatic products by liquid chromatography-tandem mass spectrometry

We developed a approach to determine residues of trichlorfon and dichlorvos in aquatic products by liquid chromatography-tandem mass spectrometry(LC-MS/MS).In our method,samples were extracted with dichloromethane.The extraction was dehydrated by anhydrous sulfate column and then concentrated.The concentrated liquid was dissolved by acetonitrile solution and defatted with n-hexane.The lower solution was determined by LC-MS/MS with ESI,using positive ion multiple reaction monitoring mode. With external standard method,the average recoveries of trichlorfon were 81.6%-90.4 %. The average recoreries of dichlorvos were 97.0%-102.6 % The relative standard of dichlorvos were all below 10.2 %. The limits of quantification were 2.5 mu g/kg.The method has great potential for routine analysis of monitoring trichlorfon and dichlorvos residues in aquatic products. It is to develop a simple, high-sensitivity detection method of trichlorfon and dichlorvos for food safety.