固相萃取-气相色谱法测定水中毒死蜱

水样中的毒死蜱经全自动固相萃取仪萃取、乙酸乙酯洗脱后，用气相色谱火焰光度检测法测定，以保留时间定性，外标法定量．结果表明：选用ENVI-18小柱萃取、乙酸乙酯洗脱，在2mL／min的过水速率下取得了良好的回收率．方法的线性范围为0．25～4．0mg／L．r为0．9998，回收率为88．6％～100．6％，相对标准偏差为2．58％～7．34％，最低定量浓度为2．5μg／L．本方法快速、灵敏、准确，并能够很好的排除干扰，可以满足水中痕量毒死蜱的测定．

Determination of Chlorpyrifos in Water Samples Using Solid-phase Extraction and Gas Chromatography

Chlorpyrifos was determined by GC-FPD after extraction by ethyl acetate using automatic solid phase extraction.Qualitative analysis was done by retention time and quantitative analysis by external standard curve.The results showed that ethyl acetate was a suitable eluent and ENVI-18 was a suitable extraction solvent.When the velocity of extraction was 2 mL/min,the extraction was optimum.The linear range of the method was 0.25~4.0 mg/L,the correlation coefficient was 0.9998,the rates of recovery were 88.6%~100.6%,the relative standard deviations were 2.58%~7.34%.The method is sensitive,accurate,be able to eliminate the interferences and suitable for determination of trace chlorpyrifos in water.