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

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=1.48×106 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 Frster nonradiative energy transfer mechanism.