Studies on the interaction between Oxaprozin-E and bovine serum albumin by spectroscopic methods

The interaction between Oxaprozin-E and bovine serum albumin (BSA) was studied by spectroscopic methods including fluorescence and UV–vis absorption spectroscopy. The quenching mechanism of fluorescence of BSA by Oxaprozin-E was discussed to be a dynamic quenching procedure. The number of binding sites n and apparent binding constant K was measured by fluorescence quenching method. The thermodynamics parameter ΔH, ΔG, ΔS were calculated. The results indicate the binding reaction was mainly entropy-driven and hydrophobic forces played major role in the binding reaction. The distance r between donor (BSA) and acceptor (Oxaprozin-E) was obtained according to Förster theory of non-radioactive energy transfer.