title: Hierarchical Polymer Brushes with Dominant Antibacterial Mechanisms Switching from Bactericidal to Bacteria Repellent.
abstract: Although polycationic surfaces have high antimicrobial efficacies, they suffer from high toxicity to mammalian cells and severe surface accumulation of dead bacteria. For the first time, we propose a surface-initiated photoiniferter-mediated polymerization (SI-PIMP) strategy of constructing a "cleaning" zwitterionic outer layer on a polycationic bactericidal background layer to physically hinder the availability of polycationic moieties for mammalian cells in aqueous service. In dry conditions, the polycationic layer exerts the contact-active bactericidal property toward the adherent bacteria, as the zwitterionic layer collapses. In aqueous environment, the zwitterionic layer forms a hydration layer to significantly inhibit the attachment of planktonic bacteria and the accumulation of dead bacteria, while the polycationic layer kills bacteria occasionally deposited on the surface, thus preserving the antibacterial capability for a long period. More importantly, the zwitterionic hydrated layer protects the mammalian cells from toxicity induced by the bactericidal background layer, and therefore hierarchical antibacterial surfaces present much better biocompatibility than that of the naked cationic references. The dominant antibacterial mechanism of the hierarchical surfaces can switch from the bactericidal efficacy in dry storage to the bacteria repellent capability in aqueous service, showing great advantages in the infection-resistant applications.
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, People's Republic of China.|University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
authors.forename: Shunjie
authors.initials: S
authors.lastname: Yan
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, People's Republic of China.
authors.forename: Shifang
authors.initials: S
authors.lastname: Luan
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, People's Republic of China.
authors.forename: Hengchong
authors.initials: H
authors.lastname: Shi
authors.affiliation: Polymer Materials Research Center and Key Laboratory of Superlight Materials & Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University , Harbin 150001, People's Republic China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, People's Republic of China.
authors.forename: Jidong
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, People's Republic of China.
authors.forename: Shuaishuai
authors.initials: S
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, People's Republic of China.
authors.forename: Yuming
authors.initials: Y
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, People's Republic of China.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yin
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development; D001422:Bacterial Adhesion; D001424:Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects*; D051379:Mice; D058105:Polymerization; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D011108:Polymers