高效液相色谱-电感耦合等离子体质谱法分析水中硒的形态

摘要

采用高效液相色谱法(HPLC)分离水中硒两种常见形态Se(Ⅳ)，Se(Ⅵ)，通过电感耦合等离子体质谱系统进行检测鉴定，由此建立了水中硒形态的分析方法。以0.15 mmol／L EDTA(钾)–0.1 mmol／L四丁基氢氧化铵–0.15 mmol／L乙酸铵–5%甲醇为流动相，调节流动相pH值至6～7，两种不同形态的硒可在4 min内得到有效分离。测定Se(Ⅳ)，Se(Ⅵ)，的线性范围为2～100μg／L，线性相关系数(r2)不低于0.999，Se(Ⅳ)和Se(Ⅵ)的检出限分别为0.01，0.05μg／L。分别以水源水、管网水等为基体进行加标回收试验，Se(Ⅳ)和Se(Ⅵ)，的回收率分别为102.3%～106.2%，104.7%～108.3%，测定结果的相对标准偏差分别为6.4%～9.6%，4.4%～7.3%(n=5)。该方法灵敏度高，具有良好的精密度和准确度，可用于环境水体中元素硒形态分析。%The method for determination of different species of selenium in water samples by high performance liquid chromatography (HPLC)–inductively coupled plasma mass spectrometry (ICP–MS) was established. The results showed that Se( Ⅳ ) and Se( Ⅵ ) could be separated within 4 min by using 0.15 mmol/L EDTA–K,0.1 mmol/L tetrabutyl ammonium hydroxide(TBAOH),0.15 mmol/L ammonium acetate and 5%methanol as mobile phase under pH 6–7. The detection linear range of Se(Ⅳ) and Se(Ⅵ) was 2–100μg/L with correlation coefficient (r2) of 0.999. The detection limits of Se( Ⅳ ) and Se( Ⅵ ) were 0.01, 0.05μg/L, the recoveries were 102.3%–106.2%,104.7%–108.3%, and the relative standard deviations were 6.4%–9.6%,4.4%–7.3%(n=5), respectively. The proposed method shows good accuracy, precision and sensitivity, which can be used for analyzing species of selenium in environment water.