荧光光谱法研究钙试剂羧酸钠与牛血清白蛋白结合反应特征

Studies on the Binding Reaction between Calconcarboxylic Sodium and Bovine Serum Albumin by Fluorescence Spectrophtometry

不同温度下,研究了钙试剂羧酸钠与牛血清白蛋白作用的荧光猝灭光谱、同步荧光光谱、三维荧光光谱和紫外可见吸收光谱特征;分别用SternVolmer方程和LineweaverBurk双倒数方程等处理实验数据,得到了26℃时反应的结合常数为7.664×104mol/L,结合位点数为1.522,结合反应的标准焓变、标准熵变和标准吉布斯自由能变分别为-58.36kJ/mol,-101.7J/K和-27.958kJ/mol;分析所得光谱,证实了在实验浓度和温度范围内,CCS与BSA反应可形成具有一定结构的复合物,获得了CCS对BSA构型的影响等重要信息。

At different temperature, the binding feature of calconcarboxylic sodium ( CCS) to bovine serum albumin(BSA) was studied by the fluorescence quenching spectra, the synchronous fluorescence spectrum and three-dimensional fluorescence spectra. The fluorescence quenching data were analyzed according to Stern-volmer equation and double-reciprocal equation. The quenching mechanism, the binding constant and the thermodynamic parameters were obtained. At 26 degrees C the binding constant and binding sites number are 7.664 X 10(4) mol/L and 1.522, respectively. The standard enthalpy change of the binding reaction, the standard entropy change and the standard gibbs change are - 58. 36 kj/mol, - 101.7 J/K, - 27.958 kj/mol, respectively. It proved that complex with certain structure had formed when CCS bond to BSA. Some useful information about the binding mode and the structural changes of BSA was also stuchied and discussed.