Spectroscopic studies on the interaction of a novel porphyrin derivative (PFP) and bovine serum albumin

Abstract

A novel porphyrin derivative (PFP) interaction with bovine serum albumin (BSA) was investigated by fluorescence and ultraviolet spectrophotometer. The experimental result revealed that a combined quenching procedure exists in the PFP–BSA system. The Stern–Volmer quenching constant (Ksv), bimolecular quenching constant (Kq), effective binding constant (Ka) were obtained at three temperatures. The thermodynamic parameters (ΔH, ΔG, and ΔS) were determined, which indicated that the binding process is spontaneous and the hydrophobic forces is playing a major role in the interaction. According to Förster non-radioactive energy transfer theory, the efficiency of energy transfer (E) and binding distance (r) were calculated, which demonstrated that there was no-radiative energy transfer happened during the whole process from PFP to BSA. Keywords: PFP· interaction, Bovine serum albumin, Fluorescence spectrophotometer, Ultraviolet spectrophotometer