固相萃取-气相色谱法检测8种有机磷农药的方法及条件优化

Method Optimization of Eight Organophosphorous Pesticides Detection by Solid Phase Extraction-Gas Chromatography

为建立一套针对性强、重复性好、操作简便的有机磷农药检测方法,通过固相萃取-气相色谱联用技术,利用正交试验对8种具有代表性结构的有机磷农药敌敌畏、氧化乐果、甲胺磷、乐果、马拉硫磷、毒死蜱、对硫磷、甲基对硫磷同时检测的气相色谱参数及固相萃取各个参数进行了全面探索和优化,全面分析了各个参数对回收率、色谱峰峰形以及灵敏度的影响。与现有农药残留检测方法相比,该方法峰形较好,灵敏度较高,分析时间缩短。方法检测限为1.1~2.5μg/L,线性范围为0.1~4mg/L,相对标准偏差为2.0%~7.4%,回收率为69.1%~108.2%,完全满足农残检测要求。

The condition of separating mixed dichlorvos, chlorpyrifos, parathion, parathion-methyl, dimethoate, omethoate, methamidophos, malathion methamidophos by solid phase extraction （SPE） and gas chromatography （GC） was developed in this paper. The orthogonal experiment design was used to define the best operation parameter, the effects of sensitivity, recovery and peak shape to obtain the optimization resolution. Comparing with methods reported, better sensitivity, peak shape and shorter analysis time were obtained. The detection limit was 1.1 μ g/L^2.5 μ g/L. The linear range was 0.1 mg/L-4 mg/L. The relative standard deviation ranged from 2.0% to 7.4%. The average recovery was in the range of 69.1%-108.2%. The method discussed could be applied for quick and accurate simultaneous determination for organophosphorous pesticides.