Abstract
Perfluorooctane sulfonate（PFOS）is the environmentally persistent compound distributed all over the world. Earlier studies suggested that PFOS is accumulated and give the adverse effects for the organism. Particularly, some studies suggested that PFOS binds to the blood plasma protein. Most of studies performed in vitro exposure experiment not in vivo condition. This study, we conducted in vivo experiments to identify PFOS binding protein in the plasma of rat. PFOS was administered intraperitoneally to Sprague Dawley rat at dose of 1 mg/kg b.w. The plasma obtained was separated by ammonium sulfate precipitation. The highest concentrations of PFOS （1507 ng/mL）and protein（20.7 mg/mL）were found in the 50-55% saturated ammonium sulfate fraction. SDS-PAGE and N-terminal amino acid sequence analysis in the 50-55% saturated ammonium sulfate fraction showed that the rat serum albumin（RSA） was identified as PFOS-binding protein. This is the first report to demonstrate that PFOS is bound to RSA under in vivo condition.
