胡椒酸丁二醇单脂与牛血清白蛋白相互作用的研究

运用荧光及紫外-可见吸收光谱法研究了胡椒酸丁二醇单酯(简称BPM)与牛血清白蛋白(BSA)的相互作用。实验结果表明,胡椒酸丁二醇单酯与BSA形成基态复合物导致BSA内源性荧光猝灭,猝灭机理主要为静态猝灭和非辐射能量转移,其猝灭速率常数为Kq为1.077×1013L/(mol.s)(25℃)、0.946×1013L/(mol.s)(37℃)。利用荧光猝灭反应测得结合常数KA为2.6×106(25℃)、3.4×106(37℃),结合位点数n为1.30(25℃)、1.33(37℃)。根据Frster能量转移理论得到结合距离r=2.92nm(25℃)、2.66nm(37℃)和能量转移效率E=0.45(25℃)、0.43(37℃)。通过热力学参数计算,确定胡椒酸丁二醇单酯与BSA的相互作用是熵增加和吉布斯自由能降低的自发过程,主要作用力是疏水作用力。

Studies on the interaction between new anti-hyperlipidemic compounds and bovine serum albumin

The interaction between butanediol piperinie mono-ester and bovine serum albumin(BSA) has been studied by fluorescence spectroscopy and UV-vis absorption spectroscopy.The experimental results showed that the fluorescence quenching of BSA by butanediol piperinie mono-ester was due to the formation of butanediol piperinie mono-ester-BSA complex through both static quenching and nonradiative energy transfer.The quenching constants(Kq) were 1.077×1013L/(mol.s)(25℃) and 0.946×1013L/(mol.s)(37℃).With the fluorescence quenching method,the binding constants(KA) were 2.6×106L/moL(25℃)and 3.4×106L/moL(37℃),and the values of binding sites(n) were 1.30(25℃) and 1.33(37℃).According to the Frster theory of non-radiation energy transfer,the binding distance(r) were 2.92nm(25℃)and 2.66nm(37℃),and the energy transfer efficiencies(E) were 0.45(25℃) and 0.43(37℃).The binding process of binding was a spontaneous molecular interaction in which entropy increased and Gibbs free energy decreased,indicating that the hydrophobic force played major role in the interaction of butanediol piperinie mono-ester and BSA.