Study of Interaction between Theophylline and Bovine Serum Albumin by Fluorescence Spectroscopy

The interaction between theophylline and bovine serum albumin(BSA) was investigated via fluorescence spectroscopy.The experimental results show that the fluorescence quenching of BSA by theophylline is due to the formation of theophylline-BSA complex through both static quenching and nonradiative energy transfer. The binding site number n and the apparent binding constant K_(A) were measured;the binding distance r and the energy transfer efficiency E between theophylline and BSA were obtained according to fluorescence resonance energy transfer;the effect of theophylline on the conformation of BSA was analyzed by means of(synchronous) fluorescence spectroscopy.