检测螃蟹中有机氯类农药残留的全自动GPC-SPE联合净化气相色谱法

Determination of organochlorine pesticide residues in Cray by automatic GPC-SPE-GC

目的建立气相色谱定量测定螃蟹中19种有机氯（OCPs）类混合农药残留的方法。方法样品用乙腈提取,环己烷-乙酸乙酯（1∶1,V/V）定容,凝胶渗透色谱（GPC）和氨基固相萃取柱（Carb/NH2）联合净化,经气相色谱（GC）检测分析。结果 19种化合物在0.02~2 mg/L内线性关系良好（r〉0.993）,各有机氯的检出限为0.04~0.31μg/kg（S/N=3）。在加标水平为20、40、80μg/kg时,方法的回收率为81.3%~116.2%,相对标准偏差为0.6%~7.5%。结论该方法选择性好、灵敏度高,样品净化效果好,适用于螃蟹中有机氯类农药的多残留痕迹测定。

[Objective] To establish a method for quantitative determination of 19 kinds of organochlorine pesticide（OCPs）residues in Cray by gas chromatography（GC）. [Methods]The samples were extracted by acetonitrile and diluted with Ethyl acetatecyclohexane（1 ∶ 1）,treated with combined purification by gel permeation chromatography（GPC） and solid-phase extraction（SPE）,and detected and analyzed by GC.[Results] The method showed a good linear relationship within the range of 0.02-2 mg/L for 19 OCPs,and the limits of detection were between 0.04 μg/kg and 0.31 μg/kg（S/N=3）. The recoveries were 81.3%-116.2%with the standard addition levels of 20 μg/kg,40 μg/kg and 80 μg/kg,and the standard deviation was 0.6 %-7.5 %.[Conclusion]The method has good selectivity,high sensibility and satisfactory purification effect,which is suitable for the determination of OCPs residues in Cray.