川芎嗪与人血清白蛋白相互作用的热力学研究

目的在模拟人体生理条件下研究川芎嗪与人血清白蛋白（HSA）的相互作用。方法采用紫外光谱法、荧光光谱法和同步荧光光谱法,研究川芎嗪与HSA的相互作用。结果紫外光谱测定：川芎嗪与HSA结合常数K=1.57×104L/moL。荧光光谱测定：川芎嗪对HSA的内源荧光有显著的猝灭作用,猝灭机制为静态猝灭。川芎嗪与HSA形成1∶1复合物,结合常数K=1.58×1 04L/moL。川芎嗪与HSA间的结合距离r=3.5 5 nm,其作用力以静电作用力为主。同步荧光光谱测定：结合位点靠近色氨酸,并使色氨酸的疏水性增强。共存金属离子（Co2＋、Zn2＋、Cu2＋等）对川芎嗪与HSA的相互作用有一定的影响。结论通过测定川芎嗪与HSA结合的相关参数,建立川芎嗪与HSA的体外结合模型。

Study on Interaction between Tetramethylpyrazine and Human Serum Albumin

Objective To study the interaction between tetramethylpyrazine and human serum albumin（HSA） under the simulative human physiological condition.Methods The interaction of HSA with tetramethylpyrazine was studied using ultraviolet spectroscopy,fluorescence spectrophotometry and synchronous fluorescence spectroscopy.Results The tetramethylpyrazine and HSA could form complex with the binding constant of K 1.57×104 L/mol tested by ultraviolet spectroscopy.The fluorescence spectrometry showed that the endogenous fluorescence of HSA had been significantly quenched by tetramethylpyrazine.A 1∶1 compound is formed between tetramethylpyrazine and HSA.The binding parameters of tetramethylpyrazine and HSA were as follows： The binding constant K was 1.58×104 L/mol,the binding distancer was 3.55 nm.The interaction was mainly driven by the electrostatic force.The synchronous fluorescence demonstrated that the binding site was closer to tryptophan residues and the hydrophobicity of tryptophan residues was increased.In addition,the effects of common metal ions on the interaction between tetramethylpyrazine and HSA were examined.Conclusion The binding of tetramethylpyrazine and HSA was demonstrated.The binding constant K was 1.58×104 L/mol,the binding distancer was 3.55 nm.