Abstract: The binding of sparfloxacin and bovine serum albumin(BSA) in aqueous solution was studied by means of fluorescence and absorbance spectra, and the interactions influenced by Fe³⁺ and Cu²⁺ were explored. Based on the Scatchard′s site binding model and fluorescence quenching, practical formulas for a small molecule ligand attaching to a bio-macromolecule are proposed. The binding parameters were measured according to the suggested models, and the binding distance, the transfer efficiency of energy between sparfloxacin and BSA were obtained in view of the Frster theory of non-radiation energy transfer. The effect of sparfloxacin on the conformation of BSA was analyzed by means of synchronous fluorescence spectroscopy.

Key words: Sparfloxacin, Bovine serum albumin, Fluorescence spectroscopy