痕量Cr(Ⅲ)的共振光散射法测定

A NEW WAY OF DETERMINING TRACE AMOUNT OF CHROMIUM THROUGH RESONANCE LIGHT-SCATTE

痕量Cr(Ⅲ)可以对十六烷基三甲基铵(CTMAB)-DNA体系的共振光散射(RLS)强度产生强烈增强作用,并且在一定范围内,其增强的幅度与cr(Ⅲ)的浓度成正比,从而建立了测定痕量Cr(Ⅲ)的RLS新方法。该法的线性范围为O.5×10-6-5.O×10-6mol/L,检测限(3δ)为7.8×10-7mol/L,对1.O×lO-6mol/L的Cr(Ⅲ)标准溶液进行连续9次平等测定,相对标准偏差为2.1％。用该法对合成水样进行了分析测定,效果良好。

The present paper aims to present a novel RLS method that has been established by its authors. Based on the enhancing effect of Cr(Ⅲ) on the resonance light-scattering system between cetyltrimethylammonium bromide and deoxyribonucleic acid (DNA), the authors have confirmed the linear nature of the RLS intensity with Cr(III) concentration in the range of 0. 5×10-6-5.0×10-6 mol/L under the optimum condition, in which the detection limit can be 7.8×10-7 mol/L with the relative standard deviation (RSD) being 2.1% for 1.0×10-6 mol/L Cr(Ⅲ) (n=9).