Interaction of Caffeine with Bovine Serum Albumin： Determination of Binding Constants and the Binding Site by Spectroscopic Methods  

作　　者：Wu, Qiong Jiang, Fenglei Li, Chaohong Hu, Yanjun Liu, Yi 

机构地区：[1]Key Laboratory for the Synthesis and Application of Organic Functional Molecules (Ministry of Education), College of Chemistry and Chemical Engineering, Hubei University, Wuhan, Hubei 430062, China [2]State Key Laboratory of Virology, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei 430072, China [3]Key Laboratory for Oral Biomedical Engineering (Ministry of Education), School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei 430072, China

出　　处：《Chinese Journal of Chemistry》2011年第3期433-440,共8页中国化学（英文版）

基　　金：Project supported by the National Natural Science Foundation of China （Nos. 20873096, 20621502, 20803019）.

摘　　要：The interaction of caffeine with bovine serum albumin （BSA） under physiological condition was investigated by fluorescence, UV-vis absorption and circular dichroism （CD） spectroscopy. Fluorescence data revealed that the fluorescence quenching of BSA by caffeine was a result of the formation of BSA-caffeine complex. The binding constants Ka at different temperatures and corresponding thermodynamic parameters △H, △G and △S were calculated. The spectroscopic measurements and the thermodynamic parameters suggested that van der Waals interaction and hydrogen bonds were the predominant intermolecular forces to stabilize the complex. The conformational change of BSA induced by caffeine has been analyzed by means of CD and synchronous fluorescence spectroscopy. Furthermore, it is observed from the probe of competitive experiments that the binding location of caffeine with BSA could be the same as warfarin binding site I of BSA, which was also revealed by fluorescence anisotropy.The interaction of caffeine with bovine serum albumin （BSA） under physiological condition was investigated by fluorescence, UV-vis absorption and circular dichroism （CD） spectroscopy. Fluorescence data revealed that the fluorescence quenching of BSA by caffeine was a result of the formation of BSA-caffeine complex. The binding constants Ka at different temperatures and corresponding thermodynamic parameters △H, △G and △S were calculated. The spectroscopic measurements and the thermodynamic parameters suggested that van der Waals interaction and hydrogen bonds were the predominant intermolecular forces to stabilize the complex. The conformational change of BSA induced by caffeine has been analyzed by means of CD and synchronous fluorescence spectroscopy. Furthermore, it is observed from the probe of competitive experiments that the binding location of caffeine with BSA could be the same as warfarin binding site I of BSA, which was also revealed by fluorescence anisotropy.

关 键 词：CAFFEINE bovine serum albumin fluorescence spectroscopy UV-vis spectroscopy site competitivebinding 

分 类 号：O657.32[理学—分析化学] Q512.1[理学—化学]