SPME-GCMSD快速检测环境介质中有机氯农药

Fast Screening of Organochlorine Pesticides in Environmental Media by Solid Phase Microextraction and GCMSD

利用SPME-GCMSD对环境介质中的"DDT"和"六六六"等有机氯农药(α HCH,β HCH,γ HCH,δ HCH,o.p′ DDT,p.p′ DDD,p.p′ DDE,p.p′ DDT)进行了多残留分析,对无溶剂化的固相微萃取与传统的索氏提取、弗罗里硅土净化的前处理方法进行了对比。结果表明:萃取时间和搅拌速率是影响萃取效率的2个主要因素,搅拌速度对DDT及其代谢物的影响较大。"六六六"的各种异构体的平衡时间较DDT要短。综合平衡各种因素确定最佳分析条件为:萃取30min,解吸5min,进样口温度为260℃。在此条件下,"六六六"的各种异构体已达到吸附平衡,而DDT及其降解产物虽未达到平衡,但由于具有较高的分配系数(K>10000),所以方法的灵敏度没有明显降低。因为没有达到分配平衡所以应严格控制萃取条件,以保证方法的重现性。固相微萃取真正实现了前处理的无溶剂化,不会对环境造成污染,而且分析简单、快速、经济。

A fast method of multiresidual analysis was developed for the determination of organocholorine pesticides(α HCH,β HCH,γ HCH,δ HCH, o p ′ DDT, p p ′ DDD, p p ′ DDE and p p ′ DDT) in environmental media (water and farm soil) using solid phase microextraction(SPME) and gas chromatography mass spectrometry detector(GC MSD) The influence of SPME extraction time, stir speed, desorption time and temperature, and gas chromatography (GC) inlet conditions for the SPME were investigated The results showed that extraction time and stir speed were main factors of influencing extraction efficiency, and stir speed had greater influence on DDTs than HCHs Extraction time of 30 min, desorption time of 5 min and desorption temperature of 260℃ were selected for SPME Since sorption balance of extraction was not obtained, process conditions and time must be controlled strictly SPME did a fast solution less alternative to conventional techniques of sample extraction SPME can be effective in analyses of semivolatile organic compounds, for sample screening or as an alternative extraction method in a formal analysis