3-羟基-6-[(4-羧基苯基)偶氮]-苯甲酸与牛血清蛋白结合反应的荧光光谱

Fluorescence Spectrometric Study on Conjugation Reaction Between 3-Hydroxy-6-[(4-Carboxyphenyl)Azo]-Benzoic Acid and Bovine Serum Albumin

采用荧光光谱研究3-羟基-6-[(4-羧基苯基)偶氮]-苯甲酸(HCPAB)与牛血清蛋白(BSA)的相互作用。通过测定298K和310K下HCPAB与BSA的荧光猝灭光谱,计算得到荧光猝灭常数、反应的结合常数、结合位点数及热力学参数,得出这种荧光猝灭机理符合静态猝灭;由Foerster能量转移机理,计算了当BSA与HCPAB比例为1:1时分子间距离r=3.18nm和能量转移效率E=0.23,并由同步荧光光谱显示HCPAB与BSA的结合位点更接近于色氨酸。

The interaction between 3-hydroxy-6-[（4-carboxyphenyl）azo]-benzoic acid（HCPAB） and bovine serum albumins（BSA） was studied by fluorescence spectra.The fluorescence quenching spectra of HCPAB on BSA were determined at temperature of 298K and 310K,and the fluorescence quenching constant,binding constant of reaction,binding site number and thermodynamical parameters were calculated,and the obtained mechanism of the fluorescence quenching was the static queching.The calculated intermolecular distance r and energy transfer efficiency E were respectively 3.18nm and 0.23,when mole ratio of BSA to HCPAB was 1：1 according to Foerster energy transfer mechanism,and the binding site numbers of HCPAB and BSA were more closed to tryptophan based on synchronous fluorescence spectra.