气相色谱法测定黄芪甘草中有机氯农药残留量

Determination of the organochorine pesticide residues in the Radix Astragali and Liquorice by the GC-ECD

[目的]建立黄芪甘草中分析有机氯农药六六六（BHC），滴滴涕（DDT），五氯硝基苯（PCNB）残留量的一种毛细柱气相色谱的分析方法．[方法]样品以丙酮提取，在氯化钠存在下，以二氯甲烷进行液液分配，用浓硫酸磺化，采用弹性石英毛细管柱Rtx-225（30m＊0．32mm＊0．10um）及电子捕获检测器（ECD），外标法计算含量．[结果]加样回收率在90．43%-104．58％，RSD％为0．05％-4．28％样品中检出的有机氯农药残留量总六六六（BHC）小于200ng／g，总滴滴涕（DDT）小于200ng／g,五氯硝基苯（PCNB）小于100ng／g，均符合国家标准．[结论]该法适用于测定黄芪甘草中的有机氯农药残留量．

Objective： To establish a simple and rapid GC method for determining the residues of organochlorine pesticide BHC, DDT, PCNB in Radix Astragali and Liqurice. Method： The samples are extracted by acetone and purified with sulfuric acid. The column is Rtx-225 （30 m×0. 32mm ×0.10um）. The electron capture detector （ECD） is used. The external standard method is used. Result： The recoveries and RSD ranged from 90.43% to 104.58% and 0.05% to 4.28% respectively, at three spiked levels. The results show that the contents of total DDT, total BHC and PCNB in Radix Astragali and Liqurice. are accordingthe permissible maximum limits of the National Standard. Conclusion： The method can be used to determine organochlonine pesticide in medicinal plant s and preprations.