(350d) Efficiency of a Mixed Copolymer As a Non-Fouling Surface

Non-specific protein binding is a very important factor in biomaterial application. To address this issue different kinds of non-fouling surfaces have been investigated. In this paper we report on the nonfouling properties of a mixed-charge polyampholyte copolymer composed of positively charged [2-(acryloyloxy) ethyl] trimethyl ammonium chloride (TMA) and negatively charged 2-carboxy ethyl acrylate (CAA) monomers. The thickness of the polymer brush coating was controlled by varying the surface initiated atom transfer radical polymerization conditions. The variation of nonspecific protein adsorption with thickness was noted. Protein conjugation was then done on each of the surfaces. The conjugation experiments clearly demonstrate that TMA:CAA copolymer is suitable for protein conjugation and nonfouling.  Fetal bovine serum (FBS) adsorption onto the surface was also characterized and indicated that nonspecific protein adsorption from complex media remains in the nonfouling range The results of this investigation indicate that TMA:CAA mixed charge surfaces show promise for biomedical application.