Pang Yue Hong, Yang Li Li, Shuang Shao Min, Dong Chuan, Thompson Michael
Institute of Advanced Chemistry, College of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China.
J Photochem Photobiol B. 2005 Aug 1;80(2):139-44. doi: 10.1016/j.jphotobiol.2005.03.006.
The interactions between bendroflumethiazide (BFTZ) and human serum albumin (HSA) have been studied by fluorescence spectroscopy. Binding constants for drug attachment to the various binding sites of HSA have been measured at different temperatures in physiological buffer solution. The effect of metal ions on BFTZ interaction with HSA was also investigated. The thermodynamic parameters, DeltaH and DeltaS, have been calculated to be 49.28kJmol(-1)>0, and 258.83Jmol(-1)K(-1)>0, respectively. The distance between HSA and BFTZ, r, was determined to be 1.47nm based on Förster's non-radiative energy transfer theory. The experimental results reveal that BFTZ has a strong ability to quench the intrinsic fluorescence of HSA through a static quenching mechanism. Furthermore, the binding constants between BFTZ and HSA are remarkably independent of temperature, and decrease in the presence of various ions, usually by about 30-55%. Hydrophobic interaction occurs between BFTZ and the sub-domain II A of HSA.
通过荧光光谱法研究了苄氟噻嗪（BFTZ）与人血清白蛋白（HSA）之间的相互作用。在生理缓冲溶液中，于不同温度下测量了药物与HSA各个结合位点的结合常数。还研究了金属离子对BFTZ与HSA相互作用的影响。计算得到的热力学参数ΔH和ΔS分别为49.28kJmol(-1)>0和258.83Jmol(-1)K(-1)>0。根据Förster非辐射能量转移理论，确定HSA与BFTZ之间的距离r为1.47nm。实验结果表明，BFTZ具有通过静态猝灭机制强烈猝灭HSA固有荧光的能力。此外，BFTZ与HSA之间的结合常数显著不受温度影响，并且在各种离子存在下会降低，通常降低约30 - 55%。BFTZ与HSA的亚结构域II A之间发生疏水相互作用。
