Studies on interaction between flavonoids and bovine serum albumin by spectral methods

The interaction between three kinds of flavonoids and bovine serum albumin (BSA) was investigated by fluorescence and UV–vis absorption spectrometry. The results indicated that flavonoids have strong ability to quench the intrinsic fluorescence of BSA by forming complexes. The binding constants, number of binding sites, thermodynamic parameters and energy transfer mechanisms were also investigated. Conformation change of BSA was observed from synchronous, three-dimensional fluorescence and circular dichroism spectrum.