超声波辅助提取—气相色谱法测定茶叶中9种有机磷农药残留

　　摘要：建立了一种超声波辅助提取-气相色谱法测定茶叶中9种有机磷农药残留的检测方法。茶叶磨碎，丙酮-正己烷（体积比为1∶1）超声波提取，活性炭小柱净化，丙酮定容，气相色谱-火焰光度法（GC-FPD）进行检测，外标法定量。以9种有机磷农药（敌敌畏、甲胺磷、乙酰甲胺磷、乐果、毒死蜱、杀螟硫磷、喹硫磷、三唑磷、水胺硫磷）为分析物，考察并优化了色谱条件、提取溶剂、净化条件和基质效应，确定了最佳试验条件。在最优试验条件下，回归方程线性范围为0.020～0.120 μg/mL，R2>0.99，方法检出限为0.004 0～0.010 0 mg/kg；9种有机磷农药残留混标于0.025、0.040和0.080 μg/mL 3个加标水平的回收率范围为80.88%～125.46%，相对标准偏差（RSD，n=6）为1.36%～10.75%。该方法准确、稳定，可满足茶叶中9种有机磷农药残留的检测要求。
　　关键词：超声波辅助提取；气相色谱法；茶叶；有机磷农药残留
　　中图分类号：O657.6；S482 文献标识码：A 文章编号：0439-8114（2016）21-5623-05
　　DOI：10.14088/j.cnki.issn0439-8114.2016.21.048
　　Determination of 9 Organophosphorus Pesticide Residues from Tea by Ultrasonic-assisted Extraction and Gas Chromatography
　　CHEN Xiao-quan， YU Xing， WU Xiao-gang， XIAO Hai-jun， LIU Bin-qiu，
　　XU Yi-yin， LING Deng-meng， SANG Shou-qiang， LIANG Jun-tao
　　（Lab of Technology Center， Menghai Tea Industry Co.， Ltd in TAETEA Group， Menghai 666200， Yunnan， China）
　　Abstract：A gas chromatographic method for the simultaneous determination of 9 organophosphorus pesticides residues in tea was established. Samples were ground，extracted with acetone-hexane（1∶1，V/V），then was cleaned-up with a activated carbon cartridge，dissolved in acetone，analyzed by GC-FPD and quantified by external standard method. With 9 organophosphorus pesticides including dichlorovos，methamidophos，acephate，dimethoate，chlorpyrifos，fenitrothion，quinalphos，triazophos and isocarbophos as analytes，the chromatographic conditions，extraction solvents，purification conditions and matrix effect were investigated and optimized to determine the optimal experimental conditions. Under the optimal experimental conditions，the method showed a good linearity（R2>0.99） in the range of 0.020～0.120 μg/mL，the limit of detections were 0.004 0～0.01 mg/kg. At the spiked levels of 0.025，0.040 and 0.080 μg/mL，the recoveries of 9 analytes were in the range of 80.88%～125.46%，and the relative standard deviations（RSDs，n=6） were 1.36%～10.75%. The method was accurate，stable，and could meet requirements for the detection of 9 organophosphorus pesticides from tea.
　　Key words：ultrasonic-assisted extraction；gas chromatography（GC）；tea；organophosphorus pesticide residues
　　茶葉是世界各国人们喜爱的饮品，也是中国主要的出口经济作物产品之一，其农药残留问题一直受到广泛关注[1]。茶叶种植中，有机磷农药因可用于防治虫害而成为最常喷施的农药种类，其半衰期相对较长[2]，对饮茶者的健康造成潜在危害。茶叶进口囯欧盟、日本等地对进口茶叶中的有机磷农药残留制定了苛刻的限量标准，中国相关部门也发布多个茶叶有机磷农药残留限量标准[3，4]。
　　国内外关于对有机磷农药残留的检测已有大量报道，常用的检测方法有气相色谱法[5-7]、气相色谱质谱联用法[8，9]、液相色谱串联质谱法[10-13]、固相微萃取-离子迁移率谱法[14]等。茶叶中的有机磷含量较低且茶叶内含物质成分丰富、基质复杂，干扰组分多，现阶段多数实验室对茶叶中有机磷农药残留的检测较为困难。探索茶叶中有机磷农药残留检测方法具有重大意义。

相关热词搜索：色谱 超声波 农药 残留 提取