分散液相微萃取-气相色谱法同时测定水中11种对鱼高毒有机磷农药残留

Dispersive liquid-liquid microextraction method coupled with gas chromatography for determination of 11 high toxic organic phosphorus pesticide in fish

目的:建立一种高灵敏度测定水中11种对鱼高毒有机磷农药残留的气相色谱分析方法。方法:向10.0 ml水样中加入100μl二硫化碳(萃取剂)和200μl丙酮(分散剂),混匀后室温静置2 min,以4000 r/min离心5 min,吸取70μl～90μl沉淀相供上机测定。结果:在1.0μg/L～500μg/L(辛硫磷在5.0μg/L～1000μg/L)范围内,11种农药具有良好的线性关系,相关系数在0.996～0.9997之间,检出限为0.3μg/L～1.0μg/L(S/N=3)。方法加标回收率在80.0%～107%之间,相对标准偏差在1.9%～6.5%之间。结论:本方法已成功应用于养殖水域实际水样的有机磷农药残留分析,操作简单、快速、环保,灵敏度高,令人满意。

Objective：A novel method was developed for the determination of 11 organic phosphorus pesticide residues in water by gas chromatography with flame thermionic detection （GC - FFD）. Methods： 100 μl of carbon disulfide （ extraction solvents） and 200 μl of acetone （ disperser solvents） were added to 10.0 μl water samples, then set at room temperature for 2 min, centrifuged at 4000 r/min for 5 rain. Finally, the sedimented carbon disulfide phase was directly injected into the GC for analysis. Results： Under the optimum conditions, a good linear relationship was obtained in the range of 1.0 μg/L - 500 μg/L（ except for phoxim ：5.0 μg/L - 1000 μg/L） of the analytes with the correlation coeficients of 0. 996 - 0. 9997 and the detection limits of 0.3 μg/L - 1.0 μg/L （ S/N = 3 ）. The recoveries for standard addition fell in the range from 80.0% to 107% and the relative standard deviations （RSD） were between 1.9% and 6.5%. Conclusion： This method has been successfully applied for the determination of or- ganic phosphorus pesticide residues in real water samples. The method was proven to be simple, rapid and environmental benign with high enrichment factor and low cost.