Abstract:The interaction between perfluorooctanoic acid (PFOA) and bovine serum albumin (BSA) in physiological buffer (pH7.4) was investigated by fluorescence quenching techniques. The results showed that PFOA could strongly quench the intrinsic fluorescence of BSA through a static quenching procedure. The binding constants (K) of PFOA with BSA at 277K, 298K and 310K were 1.06×105, 7.12×104 and 5.68×104 L/mol respectively, and the binding site (n) on BSA for PFOA was 1. The thermodynamic parameters indicated that the interaction of PFOA with BSA was driven mainly by electrostatic and hydrophobic forces. The results of synchronous fluorescence spectra showed that binding of PFOA can induce conformational changes in BSA.