Study on Interaction between Ponceau 2R and Bovine Serum Albumin by Spectroscopy and Molecular Modeling

The interaction between ponceau 2R(P2R) and bovine serum albumin(BSA) and their interaction mechanism were investigated by fluorescence spectroscopy,synchronous fluorescence spectroscopy,UV absorption spectroscopy and molecular modeling under the simulated physiological condition.The results showed that the intrinsic fluorescence of BSA was quenched by P2R,the quenching reasons were both static quenching and non-radiation energy transfer.Binding constant(Ka) and binding sites(n) at different temperatures were calculated.The results of corresponding thermodynamic parameters as well as binding distance between BSA and P2R were obtained.The synchronous fluorescence spectrometry revealed that P2R had no impact on the conformation of BSA.The result of molecular modeling indicated that P2R can bind with BSA with hydrophobic force and hydrogen bonding as the main acting force.