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建立了一种同时测定茶叶中７种拟除虫菊酯农药残留量的气相色谱方法。试样中的拟除虫菊酯农药 残留经丙酮－水（体积比８：１）体系萃取，正己烷反萃取，然后用乙腈萃取，弗罗里硅土柱净化，以ＧＣ－ＥＣＤ方 法测定，外标法定量。实验表明，试样中添加质量分数（ｗ）０．０１×１０－６～ １．０ × １０－６含量水平的联苯菊酯、氯菊 酯、氯氰菊酯、氰戊菊酯、溴氰菊酯，方法回收率为７５．０％～１０３．０％，最小检测含量０．１×１０－７（ｗ）；试样中添加 ０．００２×１０－６～ ０．２０×１０－６含量水平的甲氰菊酯，方法回收率为 ９２．０％～１００．０％，最小检测含量 ０．２×１０－８（ｗ）； 试样中添加０．００１×１０－６～０．１０ × １０－６含量水平的三氟氯氰菊酯，方法回收率为９６．０％～１０２．０％，最小检测含量 ０．１×１０－８（ｗ）。同一样品中１０次测定这７种拟除虫菊酯农药残留的标准偏差为０．００１１～０．００４７，相对标准偏 差为３．１０％～６．１５％。
A gas chromatographic method for the simultaneous determination of seven pyrethroid pesticide residues in tea was established. The pyrethroid pesticide residues in the sample were extracted with acetone-water (8: 1 by volume), back-extracted with n-hexane, then extracted with acetonitrile and purified on a Florisil column, determined by GC-ECD, Legal quantity. Experiments show that adding mass fraction (w) of bifenthrin, permethrin, cypermethrin, fenvalerate and deltamethrin at the level of 0.01 × 10-6 ~ 1.0 × 10-6, , The recovery rate was 75.0% ~ 103.0% and the minimum detection limit was 0.1 × 10-7 (w). The content of 0.002 × 10-6 ~ 0.20 × 10-6 Of the fenpropathrin, the method recovery was 92.0% ~ 100.0%, the minimum detection of 0.2 × 10-8 (w); sample was added 0.001 × 10-6 ~ 0.10 × 10-6 levels of cyhalothrin, the method recovery was 96.0% ~ 102.0%, the minimum detection limit of 0.1 × 10-8 (w). The standard deviation of the seven pyrethroid pesticide residues in the same sample was 0.0011 to 0.0047 and the relative standard deviation was 3.10% to 6.15%.