Studies of interaction between colchicine and bovine serum albumin by fluorescence quenching method

We investigated the interaction between colchicine and bovine serum albumin (BSA) by fluorescence and UV-Vis absorption spectroscopy. In the mechanism discussion, it was proved that the fluorescence quenching of BSA by colchicine is a result of the formation of colchicine-BSA complex; van der Waals interactions and hydrogen bonds play a major role in stabilizing the complex. The modified Stern-Volmer quenching constant K-a and corresponding thermodynamic parameters Delta H, Delta G, Delta S at different temperatures were calculated. The distance r between donor (BSA) and acceptor (colchicine) was obtained according to fluorescence resonance energy transfer (FRET). (c) 2005 Elsevier B.V. All rights reserved.