Department of Materials Science and Engineering, University of Utah, Salt Lake City 84112.
Polyethylene oxide(PEO)-containing nonionic polymeric surfactants were studied as a possible means to produce PEO-rich surfaces by a simple coating treatment of a common hydrophobic medical material--polyethylene. Surface tension and adsorption properties of PEO/polypropylene oxide(PPO) and PEO/polybutylene oxide(PBO) block copolymer surfactants on a hydrophobic surface (low density polyethylene, LDPE) were investigated, using the Wilhelmy plate surface tension technique and x-ray photoelectron spectroscopy(XPS). The protein resistance of the surfactant-treated surfaces was evaluated by XPS and 125I-labeled proteins. The data presented indicate that adsorption of the surfactants on LDPE is dependent on the molecular geometry of the surfactants. Adsorption of human albumin was significantly decreased on the surfactant-treated LDPE surfaces, as compared with the untreated surface. Surfactants suitable for the preparation of PEO-rich surfaces and possible mechanisms for their protein resistance are discussed.