GC-MS Determination of Residual Amounts of Prometryne and Thioencarb in Fruits and Vegetables with Dispersive Solid Phase Extraction

Residual amounts of prometryne and thioencarb in samples of fruit and vegetable were extracted by dispersive sold phase extraction (DSPE) technique with acetonitrile as extraction solvent and PSA as adsorbent.The eluate was determined by GC-MS,and external standard calibration was adopted in the determination.Under the optimized conditions,the ions with m/z 241 and 100 were selected as quantitative ions for the determination of prometryne and thioencarb respectively.Linearity ranges for both prometryne and thiencarb were between 0.05-10.0 mg·L-1.The values of recovery for prometryne and thioencarb found by standard addition method were in the ranges of 89.0%-92.0% and 92.0%-95.0%,respectively,and values of RSD′s (n=6) found were less than 7%.