浊点萃取-气相色谱法同时测定6种有机磷农药

Cloud Point Extraction for Simultaneous Determination of 6 Organophosphorus Pesticides in Environmental Samples Using Gas Chromatography

建立了浊点萃取-气相色谱法同时测定6种有机磷农药(OPPs)的分析方法。以聚乙二醇6000为萃取剂,乙酸乙酯和正己烷混合液(65∶35)作为反萃取剂,兼顾不同极性OPPs的萃取,并解决了表面活性剂因沸点高、粘度大无法进入气相检测的问题。在最佳条件下,6种OPPs在2.5~8000μg/L范围与峰面积呈现良好的线性关系(r2≥0.9958),检出限在0.8~5.0μg/L范围内,相对标准偏差(RSD)<5.18%(n=6)。该方法成功应用于测定环境水样和土壤中的6种OPPs,加标回收率为89.7%~109.9%。

A novel method termed cloud point extraction combined with gas chromatography was established for simultaneous determination of 6 organophosphorus pesticides(OPPs)with different polarities.Polyethylene glycol 6000 was used as the extractant,and a mixture of ethyl acetate and n-hexane(65∶35,V/V)was used as the back extraction agent.This method took into account the extraction of different polarities organophosphorus pesticides,and solved the issues that the surfactants could not be directly introduced to gas chromatography for detection because of its high boiling point and high viscosity.Under the optimum conditions,good linearity(r2≥0.9958)was obtained in the range of 2.5-8000μg/L.The low limits of detection were between 0.8μg/L and 5.0μg/mL,and the relative standard deviations were below 5.18%(n=6).The method has been successfully applied to the determination of 6 OPPs in environmental water and soil samples with good recoveries of 89.7%-109.9%.