催化十二烷基苯磺酸钠-钙黄绿素褪色光度法测定痕量汞(Ⅱ)

Catalytic Spectrophotometric Determination of Trace Mercury By Discoloration Reaction of Calcein and dodecylbenzene sulfonate

基于95℃及弱酸性pH=5.73条件下,十二烷基苯磺酸钠(DBS)能使钙黄绿素褪色,Hg(Ⅱ)对该褪色反应有催化作用,据此建立了催化DBS褪色光度测定痕量汞的新方法。本法线性测定范围为0.40～4.0μg/L,检出限为1.2×10^(-10)g/mL,线性回归方程为:A=0.00172+0.02683C_(Hg(Ⅱ))(μq/L),相关系数为r=0.9992。常见的阴阳离子不影响测定。本法已用于人发和水中汞含量的测定,结果满意。

A catalytic spectrophotometric determination of trace mercury by discoloration reaction of calcein and dodecylbenzene sulfonate was established. It is based on catalytic discoloration reaction of mercury( Ⅱ )with calcein and dodecylbenzene sulfonate in a slightly acidic mediue of pH=5.73 when temperature is 95 ℃. The linear regression equation is △=0.00172+0.02683CHg < Ⅱ > (i g/L), r=0.9992.The Beer's law was obeyed in the range of 0.40~4.0i g/L with the detection limit of 0.121 g/L. The molar absorptivity was 5.38×106mol-1.cm-1. The common cation and anion does not affect measurement .The method has been used for the determination of mercury( Ⅱ) in man hair and water samples with satisfactory results.