Cheng Fang-Qin, Wang Ya-Ping, Li Zhong-Ping, Dong Chuan
College of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, P.R. China.
Spectrochim Acta A Mol Biomol Spectrosc. 2006 Dec;65(5):1144-7. doi: 10.1016/j.saa.2006.01.024. Epub 2006 Jun 9.
The binding of bromsulphalein (BSP) with human serum albumin was investigated at different temperatures, 298 and 308 K, by the fluorescence spectroscopy at pH 7.24. The binding constant was determined by Stern-Volmer equation based on the quenching of the fluorescence HSA in the presence of bromsulphalein. The effect of various metal ions on the binding constants of BSP with HSA was investigated. The thermodynamic parameters were calculated according to the dependence of enthalpy change on the temperature as follows: DeltaH and DeltaS possess small negative (9.3 kJ mol(-1)) and positive values (22.3 J K(-l)mol(-l)), respectively. The experimental results revealed that BSP has a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The binding constants between BSP to HSA were remarkable and independent on temperature. The binding constants between HSA and BSP decreased in the presence of various ions, commonly decreased by 30-55%. The hydrophobic force played a major role in the interaction of BSP with HSA. All these experimental results and theoretical data clarified that BSP could bind to HSA and be effectively transported and eliminated in body, which could be a useful guideline for further drug design.
在pH 7.24条件下，于298 K和308 K这两个不同温度下，采用荧光光谱法研究了溴磺酞（BSP）与人血清白蛋白的结合情况。基于在溴磺酞存在下荧光人血清白蛋白（HSA）的猝灭，通过Stern-Volmer方程测定结合常数。研究了各种金属离子对BSP与HSA结合常数的影响。根据焓变对温度的依赖性计算热力学参数如下：ΔH和ΔS分别具有较小的负值（9.3 kJ mol⁻¹）和正值（22.3 J K⁻¹mol⁻¹）。实验结果表明，BSP能够通过静态猝灭过程强烈猝灭HSA的固有荧光。BSP与HSA之间的结合常数显著且与温度无关。在各种离子存在下，HSA与BSP之间的结合常数降低，通常降低30 - 55%。疏水作用力在BSP与HSA的相互作用中起主要作用。所有这些实验结果和理论数据表明，BSP能够与HSA结合，并在体内有效转运和消除，这可为进一步的药物设计提供有用的指导。
