SPE-GC-MS Determination of Residual Amounts of 9Pyrethroid Pesticides in Fruits

GC-MS was applied to the determination of residual amounts of 9pyrethroid pesticides in fruits after separation by solid phase extraction.The fruit sample was extracted homogeneously with acetone-H2O(5+1)mixture,and the extract was further extracted with methylene chloride.The extract obtained was then purified on graphite carbon column.DB-5capillary chromatographic column was used for GC separation and selected ion monitoring mode was adopted in MS determination.Linear relationships between values of peak area and mass concentration of the 9pyrethroid pesticides were kept in the same range of 0.1-5mg·L-1,with detection limits(3S/N)in the range of 0.000 6-0.01 mg·kg-1.The proposed method was applied to the analysis of fruit samples,giving values of recovery and RSD′s(n=5)in the ranges of 75.0%-106% and 1.6%-4.2%respectively.