气相色谱法测定水产品中拟除虫菊酯类农药残留量

Simultaneous determination of residues of pyrethroid pesticides in aquatic products by gas chromatograohy

建立水产品中联苯菊酯、甲氰菊酯、氯氟氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯6种拟除虫菊酯残留量同时测定的方法。选择环己烷:乙酸乙酯(1:1)提取,弗罗里硅土固相萃取柱净化,经丙酮:正己烷(1:9)溶剂洗脱,洗脱液吹氮浓缩,采用气相色谱外标法定量分析。结果表明:6种拟除虫菊酯类农药的检出限在1.1～2.4μg/kg之间,检测结果的相对标准偏差为1.1%～5.2%(n=5),加标回收率达到85.7%～108.1%。

Gas chromatography with electron capture detection method was developed for the determination of 6pyrethroids residues in aquatic products.The sample was extracted with cyclohexane：ethyl acetate（1：1,V：V）,separated with liquid-liquid partition and cleaned up with Florisil solid-phase extraction cartridges using acetone：n-hexane（1：9,V：V）as eluent.The eluent was blown to dryness under a stream of nitrogen,was then injected into the GC system to quantitative analysis.Under the optimal conditions,the detection limits of this method for 6pyrethroids residues were 1.1～2.4μg/kg,with the relative standard deviations ranging from 1.1% ～5.2%（n=5） and the recovery rates were from 85.7%～108.1%.