荧光法研究司他夫定与牛血清白蛋白的结合作用

在Tris缓冲溶液（pH7．1）体系中，用荧光光谱技术研究水溶液中司他夫定与牛血清白蛋白的结合作用．结果表明，司他夫定对牛血清白蛋白内源荧光产生较强的荧光猝灭作用，根据不同温度下司他夫定对牛血清白蛋白的荧光猝灭作用，证明其为静态猝灭机制，运用位点模型计算出298K，310K时其结合常数KA（分别为1．01×10^4，4．17×10^4L·mol^-1）和结合位点数n（分别为0．99，0．93），根据热力学参数确定其作用力以氢键或VanderWall＇s作用为主；蛋白质变性剂尿素的存在导致上述荧光猝灭效率减少；运用FSster偶极-偶极非辐射能量转移原理，计算了司他夫定与牛血清白蛋白的结合距离r为3．79nm．

Interaction between Stavudine and Bovine Serum Albumin by Fluorescence Spectroscopy

The interaction between stavudine and bovine serum albumin（BSA）has been studied by fluorescence spectroscopy in aqueous solution（Tris-HCl buffer, pH 7.1 ）. The results show that the fluo- rescence intensity of BSA at 345nm is quenched when stavudine is added, and that the quenching mechanism of fluorescence of BSA by stavudine is a static quenching procedure. The binding constants KA at 298K and 310K are 1.01× 10^4 and 4.17× 10^3 L·mol^-1 ,and the numbers of binding sites（ n）are 0.989 and 0. 931, respectively. The interaction between stavudine and BSA is stronger and the main binding force is hydrogen bond or Van der Waals force. The quenching efficiency decreases in presence of urea. The binding distance r（ r = 3.79nm）between stavudine and BSA is also obtained according to the Forster theory of non-radiation energy.