Highly efficient non-biofouling coating of zwitterionic polymers: Poly((3-(methacryloylamino)propyl)-dimethyl(3-sulfopropyl)ammonium hydroxide)

This work describes the formation of highly efficient non-biofouling polymeric thin films of poly((3-(methacryloylamino)propyl)-dimethyl(3-sulfopropyl)ammonium hydroxide), (poly(MPDSAH)). The poly(MPDSAH) films were generated from the self-assembled monolayers terminating in an initiator of atom transfer radical polymerization (ATRP) by the surface-initiated ATRP of MPDSAH. The poly(MPDSAH) films on a gold surface were characterized by ellipsometry, FT-IR spectroscopy, contact angle goniometery, and X-ray photoelectron spectroscopy. The copper complexes and unpolymerized monomers trapped inside the polymer brushes were completely washed out by soaking the poly(MPDSAH)-coated substrate in water at 40 degrees C for 4 days. The amount of proteins nonspecifically adsorbed onto the poly(MPDSAH) films was evaluated by surface plasmon resonance spectroscopy: the adsorption of proteins was < 0.6 ng/cm(2) on the surfaces for all the model proteins. The ability of the poly(MPDSAH) films to resist the nonspecific adsorption of proteins was comparable to that of the best known systems.