Interaction between pirenoxine and bovine serum albumin in aqueous solution

•We explored the interaction between BSA and PRX by spectroscopic methods.•The mainly binding forces are hydrophobic interactions.•The fluorescence quenching mechanism is static quenching.•The binding constants and binding sites were calculated.•The conformation of BSA was changed due to the impact of PRX.

This work concerns the interaction of prenoxine sodium (PRX) and bovine serum albumin (BSA), which was conducted by spectroscopic means: fluorescence spectra, ultraviolet–visible spectra (UV–vis) and circular dichroism spectra (CD spectra) in physiological conditions. The results revealed the PRX can quench the fluorescence of BSA remarkably in aqueous solution. The quench mechanism has been obtained after corrected the fluorescence intensities for inner filter effects. The binding constants (Ka) were calculated according to the relevant fluorescence data at different temperatures. Moreover, from a series of analyses, we have obtained the binding sites, the binding distance and binding force. The effect of PRX on the conformation of BSA has been analyzed using synchronous fluorescence under experimental conditions. In addition, the CD spectra proved that the secondary structure of BSA changed in the presence of PRX in aqueous solution.

Graphical abstractThe interaction between prenoxine sodium (PRX) and bovine serum albumin (BSA) was studied by fluorescence, circular dichroism (CD) and UV–vis spectroscopy. The quenching mechanism, binding constants, and binding distance were determined. Conformation change of BSA was also observed.Figure optionsDownload full-size imageDownload as PowerPoint slide