气相色谱法同时测定蔬菜中24种有机磷农药残留

建立了蔬菜中24种有机磷类农药残留气相色谱同时分析的方法。样品用含0.1%乙酸的乙腈提取,净化采用分散固相萃取的方式:在提取液中加入C18(ODS)、石墨炭黑、PSA等吸附剂粉末进行净化,采用DB-1701(30 m×0.32 mm×0.25μm)毛细管柱分离,FPD(P)检测。24种农药的质量分数在0.002~0.05 mg/kg时,回收率在80.1%~102.1%之间、RDS为1.4%~5.1%。各农药的检测限为:三硫磷、三唑磷为0.004 mg/kg、苯硫磷为0.01 mg/kg,其它21种为0.002 mg/kg。

Determination of 24 organophosphorus pesticide residues in vegetable by gas-chromatography

A gas chromatographic method!has been developed for the determination of 24 organophosphorus pesticide residues in vegetable. The pesticide residues were extracted from vegetable samples with acetic acid/acetonitrile (1∶999 v/v). In the purified process, the extracts were cleaned up with the addition of C_(18) (ODS)、 GCB and PSA, separated on a capillary column DB-1701 (30 m×0.32 mm×0.25 μm) and detected by FPD(P). In the range of 0.002～0.05 mg/kg, recoveries (n=6) were 80.1%～102.1%, with RSDs of 1.4%～5.1%. The detection limits of carbophenothion and triazophos are 0.004 mg/kg, EPN is 0.01 mg/kg, and the other 21 pesticides are 0.002 mg/kg. The method has the advantages of simplicity、 repeatability and sensitivity.