茶叶中乙酰甲胺磷及甲胺磷对映体的气相色谱法分离与测定  

Direct Isolation and Determination of Acephate and Methamidophos Enantiomers in Tea by Gas Chromatography

作　　者：潘蓉[1,2] 陈红平[1] 尹鹏[1,2] 汪庆华[1] 蒋迎[1] 刘新[1] 

机构地区：[1]中国农业科学院茶叶研究所农业部茶叶产品质量安全风险评估实验室,浙江杭州310008 [2]中国农业科学院研究生院,北京100081

出　　处：《分析测试学报》2014年第7期766-772,共7页Journal of Instrumental Analysis

基　　金：现代农业产业技术体系建设专项基金资助项目(nycytx-26);中国农业科学院创新团队茶叶质量与风险评估团队

摘　　要：建立了乙酰甲胺磷、甲胺磷对映体在茶叶基质中的手性拆分与定量方法。比较了2种手性柱对乙酰甲胺磷及甲胺磷对映体的分离效果，并对分离效果较优的BGB-176手性柱进行色谱条件优化。茶叶样品经改良QuEChERS法处理后，气相色谱测定，外标法定量。在0．04，0．08，0．4mg,／kg3个加标水平下，甲胺磷、乙酰甲胺磷的回收率分别为58．3％-66．4％和50．8％-57．6％，相对标准偏差（n=5）均小于7％。方法检出限为0．003—0．01mg／kg。该方法简便、可靠，满足分析要求。通过实际样品的检测，发现乙酰甲胺磷、甲胺磷对映体在茶树上存在一定的降解差异。A method of chiral separation and determination of acephate and methamidophos enantiomers in tea matrix was developed and validated. The efficiencies of two different commercial chiral columns to separate enantiomers of these two pesticides were evaluated and the gas chromatography condition of the better one （BGB - 176） was optimized. After soaked in 1 mL water, the tea samples were extracted with 10 mL acetonitrile and purified with Cls, primary secondary amine （PSA） and graphitized carbon black （GCB）, then determined by gas chromatography with the external method. The results showed that the recoveries of acephate and methamidophos enantiomers at three spiked lev- els of 0. 04, 0. 08, 0. 40 mg/kg were in the range of 58.3% - 66.4% and 50. 8% - 57.6% , re- spectively. The relative standard deviations（ n =5 ） were all less than 7%. The limits of detection of these two pesticides enantiomers ranged from 0. 003 mg/kg to 0. 01 mg/kg. The method is quick, convenient and reliable, and could meet the requirement of analysis. The result also showed that the degradations of acephate and methamidophos in tea garden were enantioselective.

关 键 词：手性分离 乙酰甲胺磷 甲胺磷 茶叶 气相色谱 

分 类 号：O657.7[理学—分析化学] F767.2[理学—化学]