毛细管电泳-电感耦合等离子体质谱法测定地下水中不同形态的砷

Speciation Analysis of Arsenic in Groundwater by Capillary Electrophoresis-Inductively Coupled Plasma Mass Spectrometry

目前砷形态分析主要采用液相色谱（HPLC）分离与电感耦合等离子体质谱（1CP—MS）、原子荧光光谱（AFS）、以及原子吸收光谱（AAS）等联用技术。与HPLC分离技术相比，毛细管电泳（CE）具有分离效率高、样品消耗少、分析速度快的优点，而ICP—MS具有元素特异性检测以及检出限极低的优势。因此，CE与ICP—MS联用成为进行包括砷在内的元素形态分析的强有力分析工具。本实验采用CE进行不同砷形态的分离，并与ICP-MS联用，实现了水样中砷形态的测定。

A method for the detection of trace As（~）, As（V）, monomethylarsonic acid（ MMA）, dimethylarsinic acid（DMA） in groundwater by capillary electrophoresis-inductively coupled plasma mass spectrometry（CE-ICP-MS） was developed. The results showed that the above four species of arsenic were baseline separated within 9 min under the optimized conditions. The detection limits （S/N = 3 ） of As（IB）, As（V）, DMA, MMA were O. 2-0.5μg/L, and the RSD （ n = 6） of the peak areas were smaller than 4.0%. The recoveries were 93%-106%. The result indicated that As（Ill） and As（V） as the main arsenic speciation existed in the groundwater of Inner Mongolia.