Study on the Mechanism of Color Changes of Azur A and Sodium Dodecyl Sulphate before Micelle Formation
CAO Wen-gen1,2,JIAO Qing-cai2
1. Department of Chemistry and Life Science，Suzhou College，Suzhou 234000, China 2. Institute of Functional Biomolecules，State Key Laboratory for Pharmaceutical Biotechnology，Nanjing University，Nanjing210093，China
Abstract：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 1.0×10-4 mol·L-1 by the relation between cSDS and ΔA498/ΔcSDS.
Key words：Sodium dodecyl sulphate;Azur A;Mechanism of color changes;Spectral probe;Critical premicelle concentration
曹稳根,焦庆才. 胶束形成前十二烷基硫酸钠与天青A变色机理的研究[J]. 光谱学与光谱分析, 2008, 28(01): 134-137.
CAO Wen-gen1,2,JIAO Qing-cai2. Study on the Mechanism of Color Changes of Azur A and Sodium Dodecyl Sulphate before Micelle Formation. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2008, 28(01): 134-137.
