Quenching of the intrinsic fluorescence of bovine serum albumin by phenylfluorone-Mo(VI) complex as a probe.

In this paper, the binding characteristics of bovine serum albumin (BSA) and phenylfluorone (PF)-molybdenum (Mo(VI)) complex have been studied by fluorophotometry. The binding constants are calculated at different temperatures. The binding distance and the energy transfer efficiency between PF-Mo(VI) complex and protein are obtained on the basis of the theory of Forster energy transfer. DeltaH and DeltaS are calculated to be -7.11 kJ mol-1 and 70.30 J mol-1 K-1, which indicate that electrostatic force plays major role in the interaction of PF-Mo(VI) complex and BSA. The experimental results show that BSA and PF-Mo(VI) complex have strong interactions and the mechanism of quenching belongs to static quenching.