【摘要】 用荧光光谱法和紫外分光光度法研究了水溶液(Tris-HCl缓冲溶液,pH7.1)中齐多夫定(ZDV)与牛血清白蛋白(BSA)的结合作用及三种金属离子(Cu2+,Mg2+,Zn2+)对其的影响.结果表明:齐多夫定及金属离子均导致BSA的内源荧光猝灭,猝灭机制均为静态猝灭;齐多夫定与BSA间存在较强结合作用,热力学参数ΔH和ΔS分别为-10.2kJ·mol-1和77.5J·mol-1·K-1(298K),表明其结合力以静电作用力为主;298K下结合常数、结合位点数和结合距离分别为6.92×105L·mol-1、1.18和2.28nm;温度升高结合常数和结合位点数减小.三种金属离子均导致ZDV与BSA的结合常数减小,结合距离增大.更多还原

【Abstract】 The interaction between zidovudine (ZDV) and bovine serum albumin (BSA) was investigated by fluorescence spectroscopy and ultraviolet-visible spectroscopy in aqueous solution (Tris-HCl buffer, pH 7.1). The effect of metal ions (Cu2+, Mg2+, Zn2+) on the interaction was also investigated. Results showed that the fluorescence intensity of BSA at 346 nm was quenched when zidovudine or metal ions were added. The quenching mechanism was a static quenching mechanism. A strong interaction exists between zidovudine and BSA. The thermodynamic parameters ΔH and ΔS were -10.2 kJ·mol-1 and 77.5 J·mol-1·K-1 at 298 K, respectively, indicating that electro-static forces played a major role. The binding constant, the number of binding site and the binding distance were 6.92×105 L·mol-1, 1.18, and 2.28 nm at 298 K, respectively. The binding constant and the number of binding sites decreased with the increase in temperature. The metal ions, Cu2+, Mg2+ and Zn2+, all decreased the binding constant and increased the binding distance for binding between ZDV and BSA.更多还原