摘要
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 method for the simultaneous determination of residues of 7 pyrethroids - bifenthrin,fen- propathrin, cyhalothrin, permethrin, cypermethrin, fenvalerate and deltamethrin-in tea was established by gas chromatography. The pyrethroids in tea were expected by acetone - water(8: 1 by volume) so- lution, followed by n -hexane reextraction. After the extract was purified through a florisil column, the pyrethroids were analyzed by GC - ECD and quantified by external standard method. Recovery rates of the pyrethroids are more than 75%, minimum detectable quantities are less than 1.0 × 10 -8(w), wheras RSD of the method is in the range of 3.10% - 6.15%.
出处
《分析测试学报》
CAS
CSCD
2000年第6期31-34,共4页
Journal of Instrumental Analysis
