胶束形成前十二烷基硫酸钠与天青A变色机理的研究

应用光谱探针技术研究了胶束形成前十二烷基硫酸钠(SDS)与天青A(AA)相互作用的吸收光谱，比较了SDS和硫酸软骨素(CS)与AA相互作用的光谱曲线，考察了乙醇和NaCl对SDS-AA复合物吸收光谱的影响，对胶束形成前SDS与AA变色反应的机理进行了研究。研究结果表明，SDS-AA反应体系呈现蓝色→紫红色→蓝色的颜色变化，主要是由于SDS有序集合体中结合态AA分子定向聚集，形成聚集体的程度不同所造成的。依据c_SDS和ΔA₄₉₈/Δc_SDS的关系，确定了SDS水溶液的临界预胶束浓度(critical premicelle concentration，CPC)，其数值为1.0×10-4 mol·L-1。

Study on the Mechanism of Color Changes of Azur A and Sodium Dodecyl Sulphate before Micelle Formation

The mechanism of color changes of sodium dodecyl sulphate(SDS) and Azur A (AA) before micelle formation was studied by spectral probe. The changes in the absorption spectra of SDS-AA and chondroitin sulfate(CS)-AA complexes were compared. The influence of ethanol and NaCl on the absorption spectra of SDS-AA complex was investigated. It was found that SDS-AA system showed color changes from blue to amaranth to blue due to the difference in the spatial orientation aggregative degree of AA binding on SDS regular aggregate. The critical concentration of premicelle formation (CPC) was found to be 1.0 x 10(-4) mol x L(-1) by the relation between c(SDS) and deltaA498/deltac(SDS).