Abstract: The present study describes the application of capillary zone electrophoresis(CZE) to investigate the interaction between bovine serum albumin and gatifloxacin, the simplified method of Hummel-Dreyer was applied and the experimental condition was established after a large number of tests. Based on the site-binding model, practical formula for small ligand molecule to bio-macromolecule has been proposed; the binding parameters were measured according to suggested model by non-linear fitting program.

Key words: Gatifloxacin, Bovine serum albumin(BSA), Capillary electrophoresis, 　Non-linear fitting