Simultaneous Determination of 67 Pesticide Residues in Soil by QuEChERS/Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry

KeyWord:ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)  QuEChERS  pesticide residues  soil

Abstract:

      A QuEChERS phase exaction coupled with ultra high performance liquid chromatography-tandem mass spectrometric(QuEChERS/UPLC-MS/MS) method was developed for the simultaneous determination of 67 pesticide residues in soil.After extraction with acetonitrile,purification with QuEChERS cartridges and dissolution with methanol,the analytes in the sample solutions were analyzed by UPLC-MS/MS on an Agilent Proshell 120 EC-C18 column with a mixture of 0ª±1% formic acid solution and acetonitrile as mobile phase by gradient elution.The mass spectrometer was operated in multiple reactions monitoring(MRM) mode under negative and positive modes.Good linearities were obtained for 67 pesticides in the concentration range of 5-500 ¦Ìg/L with correlation coefficients more than 0ª±990 and detection limits of 0ª±001-0ª±010 mg/L.Recoveries for 67 pesticides at three spiked levels of 10,50,500 ¦Ìg/kg were in the range of 58%-111%.The relative standard deviations(RSDs,n= 5) were less than 20%,and the limits of quantitation were 10 ¦Ìg/kg.The established method was simple,efficient and sensitive,and could be applied in the determination of 67 pesticide residues in soil.