title: Amino acid-based zwitterionic polymers: antifouling properties and low cytotoxicity.
abstract: A group of five amino acid containing zwitterionic vinyl monomers, based on serine, lysine, ornithine, glutamic acid, and aspartic acid, respectively, were proposed and developed for potential antifouling applications. Their polymer brushes were grafted on gold chips by surface-initiated photoiniferter-mediated polymerization. We then compared their performance in resisting protein adsorption from full human serum and plasma. All five polymers can reduce protein adsorption by more than 90% compared to the unmodified gold. The ornithine-based and aspartic acid-based poly(methacrylamide) can most strongly resist protein adsorption from serum and plasma, compared to the other three. The ability of surfaces to suppress bacterial adhesion is another criterion in evaluating antifouling properties of materials. Our results show that the five polymer-grafted surfaces can significantly suppress Escherichia coli K12 adhesion to 99% compared to the bare gold surface. The zwitterionic structure of amino acids, with homogenously distributed and balanced positive and negative charges, is responsible for the outstanding antifouling properties. Considering multiple potential applications (e.g. medical devices and drug delivery) of the antifouling materials, we further systematically evaluated the cytotoxicity of both monomers and polymer nanogels for all five materials at various concentrations. Very low cytotoxicity was observed for all tested amino acid-based monomers and nanogels, which is comparable or even lower than the traditional and some newly developed antifouling materials, which might be related to the biomimetic nature of amino acids.
authors.affiliation: a Department of Chemical and Biomolecular Engineering , The University of Akron , Akron 44325 , OH , USA.
authors.forename: Wenchen
authors.initials: W
authors.lastname: Li
authors.forename: Qingsheng
authors.initials: Q
authors.lastname: Liu
authors.forename: Lingyun
authors.initials: L
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D001422:Bacterial Adhesion / Q000187:drug effects; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D057219:Biofouling / Q000517:prevention & control*; D001798:Blood Proteins / Q000737:chemistry; D002470:Cell Survival / Q000187:drug effects; D048168:Escherichia coli K12 / Q000187:drug effects / Q000502:physiology; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D058105:Polymerization; D011108:Polymers / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D000596:Amino Acids; D001672:Biocompatible Materials; D001798:Blood Proteins; D011108:Polymers
keywords: amino acid; antifouling; bacterial adhesion; cytotoxicity; protein adsorption; zwitterionic