光谱法研究染料木素与人血清白蛋白的相互作用

用荧光猝灭光谱、同步荧光光谱和紫外-可见吸收光谱研究了染料木素与人血清白蛋白(HSA)的相互作用。结果表明染料木素对HSA的荧光猝灭作用属于二者形成复合物所引起的静态猝灭;利用Stern-Volmer方程处理实验数据，得到染料木素与HSA之间的结合常数K_A为1.00×106(27 ℃)，1.66×106(37 ℃)和5.25×106(47 ℃)。根据Frster非辐射能量转移理论，求出了染料木素与HSA之间的结合距离为2.59 nm(27 ℃)，2.65 nm(37 ℃)和2.90 nm(47 ℃)。通过计算热力学参数，可知该药物与人血清白蛋白的相互作用是一个吉布斯自由能降低的自发过程，且二者之间的主要作用力类型为静电引力，同时用同步荧光光谱探讨了染料木素对HSA构象的影响。

Study on the Interaction of Genistein and Human Serum Albumin by Spectroscopic Method

The interaction of genistein and human serum albumin (HSA) was investigated by fluorescence quenching spectra, synchronous fluorescence spectra and ultra-violet absorption spectra. The results showed that the quenching mechanism of the intrinsic fluorescence of HSA by genistein is due to the formation of genistein-HSA complex, resulting in a static quenching procedure. The binding constants (KA) were 1.00 106 (27 ℃), 1.66 106 (37 ℃) and 5.25 106 (47 ℃), respectively. According to the Frster theory of non-radiation energy transfer, the binding distances (r) were 2.59 nm (27 ℃), 2.65 nm (37 ℃) and 2.90 nm (47 ℃), respectively. The thermodynamic parameters showed that the binding power between genistein and HSA is mainly the electrostatic interaction. Synchronous spectrum was used to investigate the conformational change of HSA.