气相色谱法同时测定水中多种有机氯农药和多氯联苯

建立了一种同时测定水中16种有机氯农药(OCPs)和8种多氯联苯(PCBs)的气相色谱/电子捕获分析方法。样品经正己烷液液萃取、氮吹浓缩后,以自动不分流进样方式用气相色谱/电子捕获器检测,并对色谱条件进行优化,采用外标法定量。在较佳的试验条件下,16种OCPs和8种PCBs标准曲线的线性相关系数为0.999 0～0.999 9,方法检出限为0.001～0.002μg/L,OCPs和PCBs的平均加标回收率分别在(88.1%～107.0%)、(91.8%～104.2%)之间,相对标准偏差(RSD,n=5)分别为(2.87%～10.42%)、(3.96%～9.02%)。该方法灵敏、准确、稳定,分析时间短,适用于大批量水样中痕量有机氯农药和多氯联苯的测定。

Simultaneous Determination of Organochlorine Pesticides and Polychlorinated Biphenyls in Water by Gas Chromatography

A method for simultaneous determination of 16 organochlorine pesticides(OCPs) and 8 polychlorinated biphenyls(PCBs) in water by gas chromatography-electron capture detector(GC-ECD) was developed.Samples are extracted with n-hexane by liquid-liquid extraction and concentrated by nitrogen blowing device.The analysis is carried out by using GC-ECD in splitless mode,the chromatography condition is optimized,and the external standard method is used in quantitative analysis.Under the optimum conditions,the linear correlation coefficients for standard curves of 16 OCPs and 8 PCBs are between 0.999 0 and 0.999 9,the limits of detection are between 0.001 and 0.002 μg/L,the average recoveries of standard addition for OCPs and PCBs are 88.1% to 107.0% and 91.8% to 104.2% respectively with the relative standard deviation(RSD,n=5) of 2.87% to 10.42% and 3.96% to 9.02% respectively.The method has the advantages of high sensitivity,accuracy and stability as well as short analysis time and is suitable for the determination of trace OCPs and PCBs in a large number of water samples.