Spectroscopic investigation of the interaction of bovine serum albumin with a novel cardiac agent V-09

This study employs fluorescence spectroscopy to characterize the binding properties of a newly synthesized cardiac agent, V-09, on bovine serum albumin (BSA). This compound shows the highest cardiac activity in the whole series. The binding constants K at 25°C and 37°C are obtained, the values are 7.12×104 l mol–1, 4.66×104 l mol–1, respectively. The standard enthalpy change (ΔH0) and the standard entropy change (ΔS0) are calculated to be –27.13 KJ mol–1 and 1.854 J mol–1 K–1, which indicated that hydrophobic forces play major role in the interaction between V-09 and BSA. The binding average distance between V-09 and BSA (2.57 nm) is obtained on the basis of the theory of F？rster energy transfer.