Determination of 13 kinds of pesticides residues in green tea by gas chromatography/mass spectrometry

A GC-MS method for determination of 13 pesticide residues in green tea was developed.The pesticides in samples was extracted with n-hexane/acetone/ ethyl acetate and cleaned up with supeclean Envi-carb and florisil columns,and then detected by gas chromatography-mass spectrometry.The calibration curves for 13 pesticide residues all had good linear relationships with correlation coefficients not less than 0.997.The spiked recoveries at three concentrations of 0.10,0.50,1.00 mg/L were ranged from 85.1% to 105.3% with relative standard deviations of 5.4%～7.2%.The limits of detection were in the range of 0.002～0.015 mg/L.It was an effective method which fit for the pesticide residues analysis and has high accuracy,precision and sensitivity.