Determination of 290 Pesticide Residues in Tea by High Performance Liquid Chromatography-Tandem Mass Spectrometry

KeyWord:high performance liquid chromatography-tandem mass spectrometry  QuEChERS  pesticide residues  tea

Abstract:

      A simple and rapid method was developed for the simultaneous determination of 290 pesticide residues in tea.The sample was prepared by the modified QuEChERS(quick,easy,cheap,effective,rugged and safe) method,extracted with acetonitrile,followed by liquid-liquid partitioning formed by adding sodium chloride and anhydrous magnesium sulfate.The extract was separated on a Thermo Accucore aQ(100 mm¡Á2.1 mm,2.6 ¦Ìm) column,detected by high performance liquid chromatography-tandem mass spectrometry under multiple reaction monitoring mode and quantified by the external standard method.The calibration curves of 290 pesticide residues were linear in the range of 1.0-200 ¦Ìg?L-1 with correlation coefficients more than 0.99.The recoveries for all compounds in tea at the fortified levels of 1MRL,2MRL and 4MRL were 67%-119%.The limits of quantitation(LOQs£¬S/N¡Ý10) for 290 pesticides were less than 10.0 ¦Ìg?kg-1.The established method was successfully used for the screening and determination of real samples(such as green tea,black tea,oolong tea and pu¡¯er tea) bought at supermarket.The method was simple,rapid and reliable,and could meet the requirement for simultaneous determination of 290 pesticide residues in tea.