摘要
建立了超声波提取、分散固相萃取净化、气相色谱-电子捕获法（GC-ECD）同时测定茶鲜叶中甲氰菊酯、高效氯氟氰菊酯、氯菊酯、氟氯氰菊酯、氯氰菊酯、氰戊菊酯和溴氰菊酯7种拟除虫菊酯类农药残留的方法。样品采用V（乙酸）∶V（乙腈）=1∶99的混合溶剂超声提取,适量乙二胺-N-丙基硅烷（PSA）、十八烷基硅烷键合硅胶（C18）和石墨化碳黑（GCB）吸附剂净化,GC-ECD测定,基质外标法定量。结果表明：在0.004~2 mg/L范围内,7种拟除虫菊酯类农药的峰面积与相应质量浓度间呈良好的线性关系,相关系数均大于0.999;在0.01~0.5 mg/kg的添加水平下,平均回收率为80%~101%,日内相对标准偏差（RSD）均小于8.4%（n=6）,日间RSD均小于9.3%（n=3）;7种农药在茶鲜叶中的检出限为0.002~0.02 mg/kg,定量限为0.01~0.05 mg/kg。该方法操作简单、定量准确、溶剂用量少,对检测条件要求低,可同时测定茶鲜叶中7种拟除虫菊酯农药的残留量。
A GC-ECD method based on ultrasound assisted extraction （UAE） and dispersive solid phase extraction （DSPE） was established for simultaneous determination of 7 pyrethroid insecticides （fenpropathrin, lambda-cyhalothrin, permethrin, cyfluthrin, cypermethrin, fenvalerate, deltamethrin） in fresh tea leaves. Samples were extracted ultrasonically with V（ acetic acid） ： V（acetonitrile） = 1： 99, followed by the DSPE clean-up using primary secondary amine （PSA）, octadecylsilane bonded silica （C18） and graphitized carbon black （GCB） as adsorbents. The sample extracts were determined by GC-ECD with matrix-matched external standard method. It was shown that good linearity was obtained at concentrations of 0. 004 - 2 mg/L with correlation coefficients higher than 0. 999 for these pyrethroids. The average recoveries of the 7 pesticides in fresh tea leaves were in the range of 80% to 101% at spiked levels of 0.01 -0.5 mg/kg, with intra-day relative standard deviations lower than 8.4% （n = 6） and inter-day relative standard deviations lower than 9.3% （n = 3）. The limits of detection and quantification were 0. 002 - 0.02 mg/kg and 0.01 - 0.05 mg/kg, respectively. The method was simple, accurate, solvent saving. It was shown to be a suitable MRM method for determination of pyrethroid residues in fresh tea leaves.
出处
《农药学学报》
CAS
CSCD
北大核心
2015年第5期571-578,共8页
Chinese Journal of Pesticide Science
基金
江苏省农业科技自主创新基金项目[SCX(14)2163]
苏州市科技支撑项目(SNG201438
SNG201442)
