水中OCPs预处理方法比较

采用GC/μECD作为检测手段,比较了三种预处理方法:液液萃取、固相萃取、固相微萃取对水中OCPs的线性关系和回收情况.三种方法中,固相微萃取定量曲线的相关系数在0.9499至0.9996之间,且总体水平相对较低;液液萃取和固相萃取的相关系数在0.9948至0.9993之间.与液液萃取相比,固相萃取的回收效果更好,并且减少了人工和溶剂的消耗.采用固相萃取多次分析自来水中17种OCPs的残留水平,检出10种物质,所得浓度均未超过国内外相关水质标准.

The comparison of pretreatment methods of OCPs in water

It compared the linearity and the recovery ratio with three methods of pretreatment: liquid-liquid extraction,solid-phase extraction and solid-phase microextraction.Results indicate that the range of the correlation coefficient of the curve for quantitative analysis of solid-phase microextraction is between 0.949 9 and 0.999 6,comparatively lower than the other two methods which is from 0.994 8 to 0.999 3 in the mass.Compared with liquid-liquid extraction,the effect of the recovery efficiency of solid-phase extraction is better,and the latter also reduces labour and the consumption of solvent.We analyzed the level of the residues of 17 OCPs in tap water for several times by solid-phase extraction.The experiment data indicates that there are 10 OCPs existing in tap water.All the values of concentration accord with the target value standards of drinking water both at home and abroad.