Fluorospectrophotometric Characteristic of the Intercombination of Rifampin with Bovine Serum Albumin

Intermolecular combination of rifampin with bovine serum albumin (BSA) in aqueous solution was studied by fluorospectrophotometry. Mechanism of quenching of fluorescence of BSA by rifampin was discussed. Equilibrium constant of combination (KA) and number of combination site (n) were determined and values obtained were 3.1×10-5L·mol-1 and 1.06 respectively. By the Frster non-radiating energy transfer theory,the combination distance between the donor and acceptor as well as the efficiency of energy transfer were determined,and the value of combination distance (r) was found to be 3.89 nm. Effect of rifampin on the configuration of BSA was studied by the synchronous fluorospectrophotometry.