超声辅助-漂浮固化分散液液微萃取-气相色谱法测定茶叶中5种拟除虫菊酯类农药残留  

Ultrasound-assisted Dispersive Liquid-liquid Microextraction Based on the Solidification of a Floating Organic Droplet Followed by Gas Chromatography for the Determination of Five Pyrethroid Pesticides in Tea Samples

作　　者：高玉玲[1,2] 郭秀娟 乔石 孙鹏[1] GAO Yuling;GUO Xiujuan;QIAO Shi;SUN Peng(Heilongjiang Bayi Agricultural University, Daqing 163319, China;Heilongjiang Bayi Agricultural University of Mudanjiang Food and Bio Technology Innovation Institute, Mudanjiang 157000, China;Weihai Ocean Vocational College, Rongcheng 264300, China)

机构地区：[1]黑龙江八一农垦大学,黑龙江大庆163319 [2]黑龙江八一农垦大学牡丹江食品与生物技术创新研究院,黑龙江牡丹江157000 [3]威海海洋职业学院,山东荣成264300

出　　处：《茶叶科学》2017年第3期243-250,共8页Journal of Tea Science

基　　金：牡丹江市科技计划指导项目(Z2016n0017);大庆市科技计划指导项目(szdfy-2015-50);校内培育课题资助计划(XZR2014-17)

摘　　要：建立了超声辅助-漂浮固化分散液液微萃取(UA-DLLME-SFO)-气相色谱法(GC)测定茶叶中甲氰菊酯、氟氯氰菊酯、氯氟氰菊酯、氰戊菊酯、溴氰菊酯5种拟除虫菊酯类农药残留的方法。获得最佳试验条件为20μL十六烷(萃取剂)和800μL丙酮(分散剂),质量分数为4%的氯化钠,水相pH为4,35℃超声30 min,-3℃、10 000 r·min^(-1)离心5 min后,去除水相后经气相色谱测定。结果表明:在1~150μg·kg^(-1)范围内,5种拟除虫菊酯类农药呈良好的线性关系,相关系数均大于0.9994,在1~5μg·kg^(-1)添加水平下,平均回收率为92.3%~99.6%,日内相对标准偏差(RSD)均低于3.5%(n=6),日间相对标准偏差(RSD)均低于5.9%(n=3),5种农药在茶叶中的检出限为0.11~0.24μg·kg^(-1),定量限为0.36~0.81μg·kg^(-1)。该方法操作简便、快速、安全、成本低、重现性好,适用于茶叶样品中拟除虫菊酯类农药残留的分析。A novel ultrasound-assisted dispersive liquid-liquid microextraction based on solidification of floatingorganic droplet method(UA-DLLME-SFO)which combined with gas chromatography coupled with ECD detectorwas developed for the determination of five pyrethroid pesticides(fenpropathrin,cyfluthrin,cyhalothrin,fenvalerate,deltamethrin)in tea.The optimal liquid-liquid microextraction experiment conditions were as follows:20μLhexadecane was used as extraction solvent.After ultrasound for30min under35℃,800μL of acetone(disersivesolvent)were rapidly transferred.The NaCl Mass Fraction was4%and pH was adjusted to4.The sample solution was then centrigugated at10000r·min-1for5min under-3℃and then injected for gas chromatography analysis.It was shown that a good linearity for these pyrethroids was obtained at concentrations of1.0to150.0μg·kg-1withcorrelation coefficients higher than0.9994.The average recoveries of the5pesticides in liquid milk were in therange of92.3%to99.6%at spiked levels between1to5μg·kg-1,with intra-day relative standard deviations lowerthan3.5%(n=6)and inter-day relative standard deviations lower than5.9%(n=3).The limits of detection andquantification were0.11-0.24μg·kg-1and0.36-0.81μg·kg-1,respectively.The proposed method is simple,fast,safe,reliable and applicable for analyzing pyrethroid pesticides in tea samples.

关 键 词：超声辅助 漂浮固化分散液液微萃取 气相色谱 拟除虫菊酯 

分 类 号：O657.71[理学—分析化学] TS272.7[理学—化学]