气相色谱法快速测定叶类蔬菜中拟除虫菊酯类农药残留

建立了快速测定叶类蔬菜中拟除虫菊酯残留量的气相色谱方法。叶类蔬菜中的拟除虫菊酯经丙酮-石油醚混合液超声波辅助提取,经中性氧化铝-石墨化碳柱净化,正己烷定容,用外标法定量,以气相色谱法（GC-μECD）测定。试验结果表明：样品以0.20、0.10、0.05 mg/kg水平添加时,联苯菊酯、三氟氯氰菊酯、顺式氰戊菊酯和溴氰菊酯回收率分别为78.5%～104.3%,80.5%～106.5%,85.3%～107%,84.5%～108.5%,最低检出限为0.001 mg/L,相对标准偏差小于5%。

Rapid Determination of Pyrethroid Pesticides residue in Leafy Vegetables by Gas Chromatography

A rapid determination of pyrethroid residues in leafy vegetables by gas chromatography was developed in this paper .The pyrethroid residues in leafy vegetables was extracted with Acetone - petroleum ether mixture by ultrasound-assisted extraction, then be used the Neutral alumina-graphite carbon column to remove impurities, Constant volume of n-hexane, and determined by gas chromatography （GC-/~ECD） with the external standard method. Tests of recovery were made by addition of standard Pyrethroid to several portions of a vegetable sample at the concentration levels in 0.20 mg/kg, 0.10 mg/kg and 0.05 mg/kg, the values of bifenthrin, cyhalothrin, esfenvalerate and deltamethrin recovery found were 78.5-104.3%, 80.5-106.5%, 85.3-107% and 84.5-108.5%. Detection limit of the present method was 0. 001 mg/kg, and the values ofRSD＇ s found were less than 5%.