尿中汞的还原气化-原子吸收光谱法分析方法研究

A Study on the Determining Method of Mercury in Urine with Reduction- gasification Atomic Absorption Spectrometry

[目的]对原来研制的尿汞标准分析方法做进一步研究，建立尿中汞的还原气化-原子吸收光谱法分析的新方法。[方法]尿样中汞（尿中无机汞和经溴酸钾-溴化钾处理尿中有机汞生成的无机汞之和）以硼氢化钠还原生成汞原子蒸气，用原子吸收光谱仪测定其汞的含量。采用正交设计探讨最佳实验条件，并与原法做比较。[结果]本法的最佳实验条件为盐酸溶液浓度5％（v／v），硼氢化钠溶液和澳化剂的用量各为2ml，载气流量0．6L／min。其尿汞线性范围在0-24μg/L，线性相关系数测定为0．9997，检测限为0．014μg／L，精密度测定相对标准偏差为0．87％-6．67％，加标回收率测定为95．81％～98．61％。本方法与原法比较，标准曲线值呈高度相关，尿汞测定值无明显差别。[结论]经改进后的方法测定尿汞与原法比较有同样的效果，并且更加实用，利于推广。

[ Objective ] To further study the standard determining method of mercury in urine, and establish a new method with reduction-gasification atomic absorption spectrometry. [ Methods ] The mercury in urine, which is the total amount of inorganic mercury in urine, including those produced from organic mercury after treated by potassium bromate and potassium bromide, is determined by atomic absorption spectrophotometer after reduction into mercury atom with sodium borohydride. A design of so called orthogonal array was adopted to study the experimental conditions. It was also compared with the original method. [ Results ] The best experimental conditions for the new method were as follows ： hydrochloric acid concentration 5% ; sodium borohydride solution, potasium bromate and potassium bromide solution, 2 ml each; flow rate 0.6 L/min. The linear range of concentration was 0-24 μg/L, the detecting limit 0.014 μg/L, the correlation coefficient 0.9997, the variation coefficient of accuracy 0.87%-6.67%, and the recovery rate 95.81%-98.61%. A high correlation and no significant difference between the two determination methods were observed. [ Conclusion ] This method shows the same efficiency as the original one, however, is more practical in a wider scope.