金针菇中6种拟除虫菊酯类农药多残留的测定

建立联苯菊酯、甲氰菊酯、高效氯氟氰菊酯、高效氯氰菊酯、氰戊菊酯和溴氰菊酯6种拟除虫菊酯类农药在金针菇中的多残留分析方法。样品以乙腈为提取溶剂，弗罗里硅土柱层析净化，气相色谱-电子捕获法测定。该检测条件下，联苯菊酯、甲氰菊酯和高效氯氟氰菊酯在0.005～0.50mg/L、高效氯氰菊酯、氰戊菊酯和溴氰菊酯在0.01～1.00mg/L的范围内具有良好的线性关系，线性方程的决定系数大于0.996。添加回收实验结果表明，供试农药在添加量范围平均回收率为85.54%～102.27%，变异系数为1.24%～9.58%，联苯菊酯、甲氰菊酯和高效氯氟氰菊酯的最低检测限为5μg/L，高效氯氰菊酯、氰戊菊酯和溴氰菊酯的最低检测限为10μg/kg。该方法的准确性、精确性和灵敏度均满足农药残留分析的要求。

Multiresidue Determination of 6 Pyrethroid Pesticides in Flammulina velutipes

A method was developed for the multiresidue determination of 6 pyrethroid pesticides in Flammulina velutipes by gas chromatography with electron capture detection.Samples were extracted with acetonitrile and cleaned up on a florisil column before GC-ECD analysis.A good linear relationship with a determination coefficient above 0.996 was found for bifenthrin,fenpropathrin and lambda-cyhalothrin in the range of 0.005-0.5 mg/L and for other three pyrethroid pesticides in the range of 0.01-1.0 mg/L.The mean recoveries for the 6 pyrethroid pesticides ranged from 85.54% to 102.27% in a blank sample of Flammulina velutipes with a relative standard deviation(RSD) between 1.24% and 9.58%.The limit of detection was 5μg/L for bifenthrin,fenpropathrin and cyhalothrin and 10μg/kg for beta-cypermethrin,fenvalerate and deltamethrin.The method was accurate,precise and sensitive,and therefore could meet the requirements for pesticide residue analysis.