Controlled Protein Absorption and Cell Adhesion on Polymer-Brush-Grafted Poly(3,4-ethylenedioxythiophene) Films

Tailoring the surface of biometallic implants with protein-resistant polymer brushes represents an efficient approach to improve the biocompability and mechanical compliance with soft human tissues. A general approach utilizing electropolymerization to form initiating group (-Br) containing poly(3,4-ethylenedioxythiophen)s (poly(EDOT)s) is described. After the conducting polymer is deposited, neutral poly((oligo(ethylene glycol) methacrylate), poly(OEGMA), and zwitterionic poly([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide), poly(SBMA), brushes are grafted by surface-initiated atom transfer radical polymerization. Quartz crystal microbalance (QCM) experiments confirm protein resistance of poly(OEGMA) and poly(SBMA)-grafted poly(EDOT)s. The protein binding properties of the surface are modulated by the density of polymer brushes, which is controlled by the feed content of initiator-containing monomer (EDOT-Br) in the monomer mixture solution for electropolymerization. Furthermore, these polymer-grafted poly(EDOT)s also prevent cells to adhere on the surface.