反白藜芦醇与牛血清白蛋白相互作用的多光谱法研究

Study on the Interaction between Bovine Serum Albumin and trans-Resveratrol by Multi-spectroscopic Methods

利用荧光技术研究了抗癌药物反白藜芦醇与牛血清白蛋白的相互作用,结果证实,反白藜芦醇对牛血清白蛋白有很强的荧光猝灭作用,猝灭类型为静态猝灭。计算了反白藜芦醇与牛血清白蛋白在300、310和320 K时的结合常数、结合位点、结合距离和热力学常数等参数。由热力学参数推断两者结合过程中,起主导作用的是范德华力或氢键。同步荧光光谱和红外光谱同时说明两者结合前后蛋白质的结构发生了变化。研究还表明,金属离子Fe3+、Cu2+和Zn2+的加入使反白藜芦醇与牛血清白蛋白之间的结合常数和结合位点减小。

The interaction of trans-resveratrol（TR） and bovine serum albumin（BSA） was studied using fluorescence spectroscopy, UV - Vis spectroscopy and synchronous fluorescence spectroscopy at 300, 310 and 320 K, respectively. It was found that BSA was significantly quenched in the presence of TR. The quenching constants （Kq） obtained at those temperatures were much greater than those obtained by other quenchers, and the dynamic quenching constants （Ksv） decreased with the increase of temperature indicating that the quenching was of a static one. According to the Forster＇s energy transfer theory, the binding constants, the number of binding sites and the binding distances were calculated at 300, 310 and 320 K, respectively. The entropy change（ △H^θ） and the enthalpy change （△S^θ） were negative indicating that the Van Der Waals force and hydrogen bonds were responsible for the interaction. The synchronous fluorescence and FT - IR spectra of BSA and TR - BSA also revealed that the BSA conformation had changed in the presence of TR. The effects of Fe^3＋ , Cu^2＋ and Zn^2＋ on the TR - BSA system were examined. The results showed that the binding constants and binding site values decreased in the presence of those ions.