气相色谱-质谱法检测饮用水新生含氮消毒副产物氯代乙酰胺

Determination of Nitrogenous Disinfection Byproducts Chloroacetamides in Drinking Water by Gas Chromatography-Mass Spectrometry

建立了气相色谱-质谱(GC-MS)法检测饮用水中新生致突变含氮消毒副产物(N-DBPs)二乙酰胺(DCAcAm)和三乙酰胺(TCAcAm)的分析方法。考察了GC/MS和GC/ECD两种检测仪器及不同样品前处理技术对氯代乙酰胺(CAcAms)的检测效果。对比发现,酸催化水解+GC/ECD的分析方法容易受其它消毒副产物(DBPs)的影响,直接液液萃取(LLE)+GC/MS更适合CAcAms的分析;乙酸乙酯(ETAC)的萃取效果优于DBPs分析常用萃取剂甲基叔丁基醚(MTBE)。在选定条件下,DAcAm和TAcAm在10～1000μg/L的范围内线性关系良好,r>0.9995;方法回收率在82.0%～111.9%之间;RSD小于10%;检出限(MDL)和测定限(RQL)均低于1μg/L。

A new method for the determination of nitrogenous disinfection byproducts chloroacetamides （CAcAms） in drinking water by gas chromatography mass spectrometry （GC-MS） is described. In the method, the effects of different detecting instrument （GC/ECD and GC/MS） and sample pretreatment were investi- gated. Direct liquid-liquid extraction-GC/MS method was superior to acid-catalyzed hydrolysis ＋ GC/ECD according to recovery comparison, and extraction effect of ethyl acetate （ETAC） excels methyl tert-butyl ether （MTBE）. Good relativeity （ r 〉 0. 9995 ） was obtained when the linear range was 10 - 1000 μg/L. The recoveries of CAcAms were 82.0% -111.9%. The relative standard deviations were less than 10.0%. The determination limit is less than 1 μg/L. The advantage of this method is simple, rapid and sensitive.