Simultaneous determination of nine organophosphorus pesticides in fruits by ultra performance liquid chromatography tandem mass spectrometry

An ultra performance liquid chromatography tandem mass spectrometric method was established for the simultaneous determination of nine organophosphorus pesticides,including pyrazophos,phosalone,ethion,pirimiphos methyl,mevinphos,methidathion,phosmet,diazinon,sulfotep,in fruits.The effect of extration condition,mobile phase,and tandem mass spectrometric parameters were investigated.The sample was extracted with acetonitrile containing 1% glacial acetic acid.And PSA was used for cleaning-up.Then the analysis was carried out under the multiple reaction monitoring(MRM) mode by employing external method.The calibration curve was linear in the range of 1~18 ng/mL.The limits of detection(LOD) for the nine pesticides was 0.005 mg/kg.The average recoveries and the relative standard derivation(RSDs) of the nine pesticides were in the range of 79.6%~108.7% and 2.0%~9.8% respectively when the spiked levels was 0.005 mg/kg,0.010 mg/kg and 0.020 mg/kg.The method could be used for simultaneous quantitative determination of pyrazophos,phosalone,ethion,pirimiphos methyl,mevinphos,methidathion,phosmet,diazinon,sulfotep in fruits.