荧光光谱法研究左西孟旦与牛血清白蛋白的结合反应

Study on binding reaction between levosimendan and bovine serum albumin by fluorescence spectrometry

用荧光光谱法、分光光度法研究了水溶液中左西孟旦与牛血清白蛋白(BSA)的相互结合反应。研究表明:左西孟旦对BSA的内源荧光有较强的猝灭作用且该猝灭作用属于静态荧光猝灭作用。得出了反应的结合常数(KA=1.48×106L/mol)和结合位点数(n=1.14)。根据Frster非辐射能量转移机理,求算了给体(BSA)与受体(左西孟旦)间距离r=2.9 nm和能量转移效率E=0.33。

The binding reaction between levosimendan and bovine serum albumins （BSA） in an aqueous solution was studied by fluorescence and ultraviolet-visible absorption spectrometries. It was shown that this compound had a powerful ability to quench BSA fluorescence and the quenching belonged to static fluorescence quenching. The results show the combination constant KA = 1 .48 × 10^6 L/mol and the number of binding sites n = 1.14. The shortest binding distance （r = 2.9 nm） and energy transfer efficiency （E = 0.33） between donor （BSA） and acceptor （Levosimendan） were obtained by Foerster nonradiative energy transfer mechanism.