A gas chromatography triple quadrupole mass spectrometry(GC-MS/MS) with accelerated solvent extraction was developed for the determination of 20 organophosphorus pesticides residues in Chinese wolfberry.The samples were first extracted with acidified acetonitrile-dichloromethane(4∶1

by volume)

then purified on a Cleanert TPH solid phase extraction column

next concentrated by rotary evaporation and dried with nitrogen

and finally analyzed by GC-MS/MS.The experimental conditions such as extraction solvent

temperature and rinse volume were optimized.Results showed that the calibration curves for 20 pesticides were linear in the range of 1-500 μg/kg with their correlation coefficients(r2) of 0.999 0-0.999 8.The spiked recoveries at three levels of 20

40 and 100 μg/kg were in the range of 70.0%-82.9% with the relative standard deviations(RSDs

n=5) of 0.6%-8.5%.The limits of quantitation of the method ranged from 1.0 μg/kg to 15.0 μg/kg.The method is simple and accurate

and is suitable for the determination of organophosphorus pesticide residues in Chinese wolfberry.