生活饮用水中乙草胺的固相萃取-气相色谱-质谱联用测定法

Determination of acetochlor in drinking water by solid phase extraction-gas chromatography-mass spectrometry

目的建立生活饮用水中乙草胺的固相萃取(SPE)-气相色谱-质谱(GC-MS)联用测定法。方法生活饮用水经全自动固相萃取系统进行萃取,洗脱液浓缩至1.0 ml,用气相色谱-质谱联用仪测定,内标法定量。通过实验优化进样流速、进样体积和洗脱流速,从检出限、精密度、准确度及加标样品的测定结果评价本方法的分析效果。结果乙草胺在10~250μg/L范围内有良好的线性关系,相关系数为0.9995;乙草胺的检出限为0.0062μg/L,定量下限为0.025μg/L;内标法所得加标回收率分别为95.2%~99.8%,RSD为1.3%~1.6%。结论该方法具有较高的精密度和准确度,且目标峰和内标分离度好,适用于生活饮用水中乙草胺的检测。

Objective To develop a method for the determination of acetochlor in drinking water by solid-phase extraction(SPE)-gas chromatography-mass spectrometry(GC-MS).Methods The samples of drinking water were extracted by automatic solid phase extraction system,the eluent was concentrated to 1.0 ml,determined by gas chromatography-mass spectrometry,and quantified by internal standard method.By optimizing injection flow rate,volume and elution flow rate,the results of detection limit,precision,accuracy and standard sample were evaluated.Results Acetochlor had a good linear relationship in the range of 10-250μg/L,and the correlation coefficient was 0.9995.The limit of detection of acetochlor was 0.0062μg/L,and the limit of quantitation was 0.025μg/L.The recoveries of internal standard method were in the range of 95.2%-99.8%,the relative standard deviations were in the range of 1.3%-1.6%.Conclusion The method has high precision and accuracy,good separation of target peak and internal standard,and is applicable to the determination of acetochlor in drinking water.