中草药中40种农药残留的气相色谱-质谱分析

建立了一种同时测定中草药中有机磷、有机氯、拟除虫菊酯和氨基甲酸酯等四大类40种农药残留量的分析方法。通过比较三氯甲烷、乙腈、正己烷、乙酸乙酯和丙酮等多种溶剂的提取效果,确定三氯甲烷和丙酮为提取溶剂;提取的样品经弗罗里硅土净化,用GC-MS选择离子模式进行测定,采用外标法进行定量。40种农药在65min内达到理想的分离效果。以2个添加水平测定样品的回收率和相对标准偏差,回收率在88.6%和107.1%之间,RSD均低于8.0%。各农药检测限为0.5～37.5μg/kg,定量限为1.4～112.5μg/kg。采用该方法,对百合、刀豆、菊花、黄芪、人参、当归、车前草7种不同种类的中草药进行了实际检测,均发现一定量的农药残留。该方法简便、快速、准确、灵敏,且重现性好,可用于中草药中多种农药残留的同时测定。

Multi-residues Analysis of Pesticides in Herbal Medicines by Gas Chromatography-mass Spectrometry with SIM Model

An analysis method based on gas chromatography-mass spectrometry(GC-MS) was developed to determine 40 pesticides including organochlorinates,organophosphates,synthetic pyrethroids and carbamate. Sample was extracted with mixture of chloroform and acetone and the extract was further purified through a Florisile column chromatography. The prepared sample was then analyzed using GC-MS with selective ion monitoring(SIM)mode. 40 pesticides were well separated within 65 minutes,and all relative standard deviations(RSD)were less than 8.0%,and the recoreries were 88.6%～107.5%. The limits of detection(LODs) ranged from 0.5～37.5 μg/kg under the signal noise ratio 3:1,and the limits of quantitation(LOQs)were 1.4～112.5 μg/kg. The method is simple,rapid,sensitive,and of good repeatability. It is suitable for the multiresidues analysis of pesticides in herbal medicines.