加速溶剂萃取-气相色谱测定茶叶中多种农药残留

Determination of Pesticide Residues in Tea by Accelerated Solvent Extraction-Gas Chromatography

目的建立一种加速溶剂萃取(ASE)-气相色谱(GC)同时测定茶叶中三氯杀螨醇(有机氯类)与多种除虫菊酯类农药残留的新方法。方法样品用环己烷∶乙酸乙酯(1∶1,V/V)提取,提取液经florisil固相萃取柱净化后,采用气相色谱-电子捕获检测器(GC-ECD)进行检测。结果各农药在0.01、0.05、0.25mg/kg3个添加水平上的平均回收率都在90%以上,RSD在0.3%～3.8%之间。结论该方法快速、溶剂用量少、重现性好,能够满足茶叶中有机氯与拟除虫菊酯类农药残留的检测要求。

Objective To determine multi-residues of organochlorines pesticides （OCPs） and pyrethroid pesticides in tea by accelerated solvent extraction-gas chromatography （ ASE-GC ） method. Method Samples were extracted with thiacyclohexane-ethyl acetate （1 ∶ 1,V /V）. The extracts were purified by solid-phase extraction by using florisil as a adsorbent and were detected by gas chromatography-electron capture detection （ GC-ECD）. Results The recoveries of standard addition at the levels of 0. 01,0. 05 and 0. 25 mg /kg were more than 90% ,the relative standard deviations （RSD） were in the range of 0. 3% -3. 8% . Conclusion The method of ASE-GC is fast,low cost and in good reproducibility,which can be used for the determination of multi-residues of organochlorine and pyrethroid pesticides in tea.