A method was established for the determination of 508 pesticide reisdues in Panax notoginseng by liquid chromatography-tandem mass spectrometry(LC-MS/MS).The samples were extracted by modified QuEChERS method

followed by the clean up of d SPE extraction.The extract was determined by LC-MS/MS in multi reaction monitoring(MRM) mode

and quantified by the internal standard method.There were linear relationships for the 508 pesticides in the range of 0005-04 mg/L with limits of detection(LOD) of 0005-01 mg/kg.Except for 8 pesticides

the recoveries for other 500 pesticides at spiked level of 100 μg/kg were in the range of 502%-117%with relative standard deviations(RSD) not more than 15%

in which

the recoveries for 468 pesticides were in the range of 70%-120%.With the advantages of simplicity

rapidness

good sensitivity and accuracy

the method could meet the requirements for multiple pesticide residues analysis

and is suitable for the determination of 508 pesticide residues in Panax notoginseng.