双波长共振散射比率法测定十二烷基苯磺酸钠的研究

Determination of SDBS by dual-wavelength resonance light scattering ratio method

基于表面活性剂SDBS与罗丹明B的结合反应发展了一种测定SDBS的双波长共振散射比率法。在BR缓冲溶液介质中,SDBS能与RB发生反应,其位于373.0nm的特征共振光散射信号大大增强。通过分别测定I373.0和I685.0/I650.0来检测SDBS,当罗丹明B的浓度为1.0×10-4 mol/L时,以I373.0为测定点的共振光散射方法所得到的线性范围和检出限分别为0.018～80μmol/L和1.76 nmol/L。而用I685.0/I650.0的散射强度之比来检测SDBS时,其得到的线性范围和检出限分别为0.002～100μmol/L和0.23 nmol/L。表明后者即双波长共振散射比率法明显优于前者。

A dual-wavelength resonance lighting scattering（DW-RLS）ratio method is developed to detect surfactant SDBS based on its bindings with Rhodamine（RB）.In Britton–Robinson buffer controlled medium,SDBS could interact with RB,displaying significantly enhanced RLS signals.By measuring the RLS signals characterized at 373.0 nm（I373.0）and the RLS intensity ratio（I685.0/I650.0）,respectively,SDBS over a wide dynamic range of content could be detected.Typically,when RB concentration is kept at 1.0 × 10-4 mol/L,using I373.0 could detect SDBS over the range of 0.018–80 μmol/L with the limit of 1.76 nmol/L,while using I685.0/I650.0 could detect SDBS over the range of 0.002–100 μmol/L with the limit of 0.23 nmol/l.Showing the latter so-called DW-RLS ratio method is obviously superior to the former one.