Interaction between fasudil hydrochloride and bovine serum albumin: spectroscopic study.

The interaction between fasudil hydrochloride (FSD) and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopy under imitated physiological conditions. The Stern-Volmer quenching model has been successfully applied and the results revealed that FSD could quench the intrinsic fluorescence of BSA effectively via static quenching. The binding constants and binding sites for the BSA-FSD system were evaluated. The corresponding thermodynamic parameters obtained at different temperatures indicated that hydrophobic force played a major role in the interaction of FSD and BSA. The distance between the donor (BSA) and the acceptor (FSD) was obtained according to fluorescence resonance energy transfer (FRET). Synchronous fluorescence spectroscopy and FT-IR spectra showed that the conformation of BSA was changed in the presence of FSD. Copyright © 2015 John Wiley & Sons, Ltd.