Rapid GC-MS/MS Determination of Residual Amounts of 20 Organophosphorus Pesticides in Fruits and Vegetables

GC-MS/MS was applied to the rapid determination of residual amounts of 20 organophosphorus pesticides in fruits and vegetables. The sample of fruit or vegetable was extracted with acetonitrile. NH₂/Carb was used as adsorbent. The HP-5MS capillary chromatographic column was used for GC separation and the full-scanning mode and the multiple reaction monitoring mode were adopted in MS determination. Linear relationships between values of peak area and mass fraction of the 20 organophosphorus pesticides were kept in the same range of 5-2 000 μg·kg^-1, with detection limits(3S/N)in the range of 0.11-1.02 μg·kg^-1 and lower limits of determination (10S/N) in the range of 0.26-3.51 μg·kg^-1. On the base of blank sample, test for recovery was made by standard addition method; values of recovery found were in the range of 83.8%-107%, with RSD's (n=6) in the range of 2.1%-14%.