巢湖水中7种有机磷和12种有机氯农药SPME检测技术研究

通过优化萃取时间、温度、离子强度和盐离子浓度等条件,建立了巢湖水中7种有机磷农药和12种有机氯农药的固相微萃取技术检测条件。试验结果表明,有机磷农药微萃取的优化条件为:采用PA纤维头,萃取温度为20℃、萃取时间为60 min、氯化钠浓度为35%,pH为7;有机氯农药微萃取的优化条件为:采用PDMS纤维头,萃取温度为60℃,萃取时间60 min,氯化钠浓度为5%,pH为7。在优化条件下,利用SPME对巢湖水中的有机磷、有机氯农药进行添加回收试验。结果表明,有机磷农药平均添加回收率在80.09%～118.82%之间,变异系数在0.23%～15.62%之间;有机氯农药平均添加回收率在72.80%～103.80%之间,变异系数在1.24%～11.69%之间。符合农药残留分析要求。

Determination of organophosphorus and organochlorine pesticides in Chaohu Lake by solidphase microextracion with gas chromatography

A method for the determination of organophosphorus and organochlorine pesticides in Chaohu Lake by so1idphase micro extraction(SPME) with gas chromatography was developed.The experimental condi-tions of SPME such as extraction time,pH and ion strength of the extraction solution,adsorption temperature were optimized.The result showed optimal experimental conditions for determining 7 kinds of OPPs(organo-phosphorus pesticides) are using PA(polyacrylate),adsorption at 20℃,extraction for 60 min,pH 7 and ion strength of 35%.For 12 kinds of OCPs(organochlorine pesticides),using PDMS(polydimethylsiloxane)fiber,adsorption at 60℃,extraction for 60 min,pH 7 and ion strength of 5%.The method was used for the determina-tion of OPPs and OCPs in spiked water of Chaohu Lake.The recoveries of OPPs and OCPs ranged from 80.09% to 118.82%,and 72.80% to 103.80%,respectively.;coefficients of variation ranged from 0.23% to 15.62%,and 1.24% to 11.69%,respectively.This method can meet the need of the pesticide residue analysis.