GC-MS/MS Determination of Residual Amounts of Pesticides in Ginger

Gas chromatography in hyphenation with tandem mass spectrometry(GC-MS/MS) was applied to the determination of residual amounts of 25 pesticides in ginger.The sample was extracted with acetonitrile,which was concentrated and purified by NH2/Carbon solid-phase extraction column.The eluate was evaporated to near dryness and diluted to a definite volume with mixture of n-hexane and acetone(9+1),and separated on the VF-5MS column.The eluate was used for tandem MS analysis.Linear relationships between values of peak area and mass concentration of the 25 pesticides were obtained in the same range of 0.020-0.500 mg·L-1,with detection limits(3S/N) in the range of 0.2-10.0 μg·kg-1.Test for recovery were made by addition of standard at 2 different concentration levels,values of recovery for most of the pesticides found were in the range of 77%-130%,with values of RSD′s(n=5) less than 20%.