伊文思蓝与牛血清白蛋白相互作用的研究

Studies on the Interaction Between Evansblue and Bovine Serum Albumin by Fluorescence Spectrophotometry

利用荧光光谱和紫外吸收光谱研究了伊文思蓝(Evans blue,EB)与牛血清白蛋白(Bovine serum albumin,BSA)的相互作用。伊文思蓝与牛血清白蛋白作用,使牛血清白蛋白的荧光发生猝灭,利用Stern-Volmer方程和荧光寿命的测定,确定了伊文思蓝对牛血清白蛋白的荧光猝灭为静态猝灭和非辐射能量转移。实验测得伊文思蓝与牛血清白蛋白的结合常数KBSA-EB为1.122×106L·mol-1,结合点数n为0.994;根据Foerster非辐射能量转移理论,得到伊文思蓝与牛血清白蛋白之间的能量转移效率E为0.276,作用距离r为3.14nm。同时,利用同步荧光光谱研究了牛血清白蛋白的构象变化。

The interaction of evansblue（EB） and bovine serum albumin （BSA）was studied by fluorescence spectroscopy and ultraviolet spectroscopy. The experimental results showed that EB could quench the inner fluorescence of BSA by forming the BSA-EB complex. It was found that both static quenching and non-radiation energy transfer led to the fluorescence quenching. The binding constants （K） between EB and BSA were 1.122×10^6L·mol^-1, and the binding sites （n） were 0. 994. According to Foerster theory of non-radiation energy transfer the binding distance（r=3.14nm） and the efficiency of energy transfer （E = 0. 276） were also obtained. The effect of EB on the conformational change of BSA was also analyzed by synchronous fluorescence spectroscopy.