防己诺林碱与牛血清白蛋白相互作用的研究

在不同温度下，用荧光猝灭光谱、同步荧光光谱和紫外-可见吸收光谱，研究了防己诺林碱与BSA相互作用的光谱学行为。防己诺林碱对BSA有较强的荧光猝灭作用。根据不同温度下防己诺林碱对BSA的荧光猝灭作用，利用Stern-Volmer方程处理实验数据，表明防己诺林碱对BSA的荧光猝灭作用属于静态猝灭。根据Frster非辐射能量转移理论计算出了防己诺林碱与BSA间的结合距离R(27 ℃ 2.51 nm; 37 ℃ 2.72 nm; 47℃ 2.89 nm)、结合常数K_A(27 ℃ 1.05×105 L·mol-1; 37 ℃ 3.31×105 L·mol-1; 47 ℃ 7.24×105 L·mol-1)及对应温度下的热力学参数。热力学数据表明二者主要靠疏水作用力结合，同时用同步荧光光谱探讨了防己诺林碱对BSA构象的影响。

Study on the Interaction between Fangchinoline and Bovine Serum Albumin

The binding reaction of fangchinoline with bovine serum albumin was studied at different temperatures by fluorescence quenching spectra, synchronous fluorescence spectra and ultra-violet spectra. It was shown that fangchinoline has a strong ability of quenching the fluorescence of BSA. The Stern-Volmer curve of the fluorescence quenching of BSA by fangchinoline indicated that the quenching mechanism of fangchinoline to BSA was a static quenching. According to the Frster theory of non-radiation energy transfer, the binding distances (r) at different temperature were 2.51 nm (27 ℃), 2.72 nm (37 ℃) and 2.89 nm (47 ℃), respectively, while the binding constants (K_A) were 1.05×105 L·mol-1 (27 ℃), 3.31×105 L·mol-1 (37 ℃), and 7.24×105 L·mol-1 (47 ℃), respectively. The thermodynamic parameters showed that the interaction of fangchinoline and BSA was mainly driven by hydrophobic force. Synchronous spectrum was used to investigate the conformational changes of BSA.