高效液相色谱-电感耦合等离子体质谱联用测定水中烷基汞

Determination of Alkyl Mercury in Water by HPLC-ICP-MS with Solid Phase Extraction

研究提出了高效液相色谱与电感耦合等离子体质谱法联用同时测定水中甲基汞、乙基汞的方法。水样通过固相萃取富集、高效液相色谱分离后，用电感耦合等离子体质谱法测定甲基汞、乙基汞的含量。甲基汞、乙基汞均在0．8—100ng／L范围内与响应信号呈现良好的线性关系，方法检出限分别为0．2、0．5ng,／L。在优化建立的分析条件下，开展了1、20ng／L两种浓度的加标回收方法评估研究，结果表明地表水、生活饮用水、污水厂出水等三种水样加标回收率在71．2％～105．2％之间，相对标准偏差为6．4％～9．4％（n=5）。该方法操作简便、灵敏度高，可满足城市水系统中烷基汞痕量检测的要求。

The method for determination of methyl mercury and ethyl mercury in water by high- performance liquid chromatography-inductively coupled plasma-mass spectrometry （HPLC-ICP-MS） with solid phase extraction was investigated. After solid phase extraction and high performance liquid chromatography separation, methyl mercury and ethyl mercury were detected by ICP-MS. A good linear ralation between the response signal and concentrations of methyl mercury and ethyl mercury existed in the range from 0.8 ng/L to 100 ng/L with the method detection limits of 0.2 ng/L and 0.5 ng/L respectively. Under the optimized method, standard addition recovery method was evaluated with concentrations of 1 and 20 ng/L. The results showed that the recoveries for surface water, domestic drinking water and treated effluent from WWTP were 71.2% to 105.2%, and the relative standard deviations ranged from 6.4% to 9.4% （ n = 5 ）. The method is simple and sensitive. It can meet the requirements of trace detection of alkyl mercury in urban water system.