荧光光谱法研究头孢孟多脂与牛血清白蛋白的相互作用

模拟生理条件下,用荧光光谱法和紫外-可见吸收光谱法研究头孢孟多酯和牛血清白蛋白(BSA)结合反应的特征。研究表明:头孢孟多酯与BSA形成复合物,从而猝灭BSA的内源性荧光,该过程为静态猝灭过程。根据SternVolmer方程得出不同温度下结合位点数n和结合常数Ka;结合位点位于BSA的亚结构IIA中。通过计算相应的热力学参数,确定头孢孟多酯与BSA之间的作用力主要为静电作用力。利用同步荧光光谱探讨了头孢孟多酯与BSA作用前后白蛋白的构型变化。Hill系数nH1,表明头孢孟多酯有弱的负协同作用。此研究不仅对于揭示体内药物动力学问题和指导临床合理用药具有一定意义,而且对药物分子设计及新药开发等也具有重要指导意义。

Study on interaction between cefamandole and bovine serum albumin by fluorescence spectroscopy

The interaction between cefamandole and bovine serum albumin （BSA） was studied with fluorescence spectra and UV-visible absorption spectra in the presence of simulating physiological systems. It showed that the complex for mated by BSA and cefamandole lead to the static quenching of the intrinsic fluorescence of BSA. The binding site number n and apparent binding constant Ka were measured according to the Stern-Volmer equation. The primary binding site for cefamandole was located at site I in subdomain IIA of BSA. The author also confirmed that the main sorts of binding force between cefamandole and BSA was the electro-static force. Meanwhile, synchronous fluorescence was used to investigate the structure change of BSA before and after the introduction of cefamandole. The values of Hill＇s coefficients were less than 1, which indicated that there was some negative cooperative effect. It is not only valuable to reveal the pharmacokineties, clinical therapy, but also guiding significance for drug design and development of new drugs.