气相色谱法测定蔬菜中8种有机磷农药的残留量

Simultaneous determination of 8 kinds of organophosphorus pesticide residues in vegetables by gas chromatography

目的采用气相色谱法同时测定蔬菜中甲胺磷、氧化乐果、乐果、甲基对硫磷、毒死蜱、对硫磷、水胺硫磷和三唑磷8种有机磷农药的残留量。方法样品经乙腈提取后,经Agilent DB-17色谱柱分离,采用火焰光度检测器检测,以外标法定量。结果毒死蜱和乐果在0.25~5μg/m L,其他6种有机磷在0.025~0.5μg/m L浓度范围内具有良好的线性关系,检出限为0.006~0.023μg/m L;8种有机磷农药的回收率为97.6%~104.8%,相对标准偏差为0.98%~1.67%。结论该方法精确可靠,重复性、稳定性和分离效果好,可用于测定蔬菜中有机磷农药的残留量。

Objective To establish a method for the determination of methamidophos, omethoate, dimethoate, parathion-methyl, chlorpyrifos, parathion, isocarbophos and phentriazophos in vegetables by gas chromatography. Methods Vegetable samples were extracted with acetonitrile, separated by an Agilent DB-17 column, and then detected bu flame photometric detector （FPD） using the external standard method for quantification.Results The method showed good linearities in the ranges of 0.25~5 μg/mL for chlorpyrifos and dimethoate and 0.025~0.5 μg/mL for other 6 kinds of organophosphorus. The limits of detection were 0.006~0.023μg/mL. The recoveries of 8 kinds of organophosphorus pesticides were 97.6%~104.8% with relative standard deviations （RSDs） of 0.98%~1.67%. Conclusion This method has good accuracy, reproducibility, stability and separation, which can be used for determination of organophosphorus pesticide residues in vegetables.