气相色谱-串联质谱法测定辣根中37种农药残留量

GC-MS/MS Determination of Residual Amounts of 37 Pesticides in Horseradish

采用气相色谱-串联质谱法测定辣根中37种农药的残留量。样品用乙酸乙酯-乙腈(15+85)混合液提取,经N-丙基乙二胺(PSA)、活性炭和无水硫酸钠净化,高速离心所得上清液浓缩后用1.0 mL甲苯定容。经VF-5MS色谱柱分离,串联质谱测定,内标法定量。37种农药的测定下限(10S/N)在0.005~0.1 mg·kg^(-1)之间。以空白辣根样品为基体,加入4种不同浓度的标准溶液进行回收试验,其回收率在61.1%~120%之间,相对标准偏差(n=7)在2.9%~19%之间。

GCMS/MS was applied to the determination of residual amounts of 37 kinds of pesticides in horseradish. The sample was extracted with a mixture of ethyl acetate and acetonitrile （15 ＋ 85）, and the extract was purified with PSA, activated carbon and anhydrous sodium sulfate After speedy centrifugation, the supematant was concentrated and made up to 1.0 mL with methylbenzene. VF5MS column was used for separation, and MS/MS was used for determination with internal standard method for quamificatiorL Values of lower limits of detemlination （10S/N） found were in the range of 0. 005--0. 1 mg · kg 1. Tests for recovery were made by addition of pesticide standards at 4 different concentration levels to blank sample of horseradish as matrixes, values of recovery found were in the range of 61.1%- 120%, with values of RSD＇s （n=7） in the range of 2. 90/oo to 19~/00.