共振光散射法测定镉的应用研究

Determination of Cadmium Ions by Resonance Light Scattering and Its Application

在十二烷基硫酸钠（SLS）存在的条件下，基于KI和Cd（Ⅱ）形成[CdI4]^2-络阴离子后与四丙基溴化铵（TPAB）结合形成离子缔合物使共振光散射（RLS）信号强度明显增强，建立了运用共振光散射技术测定水样中镉含量的新方法．研究了四丙基溴化铵-碘化钾-镉体系的共振光谱特征，在364nm处体系的散射光强度最大．在最佳实验条件下，体系的共振光散射强度与Cd（Ⅱ）浓度在0．08～4．0μg·mL^-1范围内呈良好的线性关系，检出限可达2．80ng·mL^-1.用此方法测定合成水样中的Cd（Ⅱ），操作简便快速，回收率在96．4％～105．7％之间，结果令人满意．

A new method has been developed for the determination of cadmium based on the enhanced resonance light scattering （RLS） intensity resulting from the complex formed by [CdI4 ]^2- and tetrapropyl ammonium bromide （TPAB） in the presence of sodium dodecyl sulphate （SLS）. The characteristics of RLS spectra of ion-association complex have been investigated,and the maximum RLS peaked at 364 nm. Under the optimum condition, there is a good linear relationship between the IRLS and the concentration of cadmium in the range of 0.08-4.0 μg/mL, with a detection limit of 2.80 ng· mL^-1. This method is simple and speedy. It is successfully applied to determine cadmium in synthesized sample and the results are satisfactory, with the recovery between 96.4% -105.7 %.