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

GC-MS was applied to the determination of residual amounts of 9 pyrethroid 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-5 capillary 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 9 pyrethroid pesticides were kept in the same range of 0.1-5 mg·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.