作者：Tingwu Liu, Shunjie Yan, Rongtao Zhou, Xu Zhang, Huawei Yang, Qiuyan Yan, Shifang Luan*, et al.,
关键字：light living graft polymerization, micrometer-scale thickness
论文来源：期刊
具体来源：ACS Applied Materials Interfaces
发表时间：2020年

Abstract：

Surface-tethered hierarchical polymer brushes fifind wide applications in the development of antibacterial surfaces due to the well-defifined spatial distribution and the separate but complementary properties of difffferent blocks. Existing methods to achieve such polymer brushes mainly focused on inorganic material substrates, precluding their practical applications on common medical devices. In this work, a hierarchical polymer brush system is proposed and facilely constructed on polymeric substrates via light living graft polymerization. The polymer brush system with micrometer-scale thickness exhibits a unique hierarchical architecture consisting of a poly(hydroxyethyl methacrylate) (PHEMA) outer layer and an anionic inner layer loading with cationic antimicrobial peptide (AMP) via electrostatic attraction. The surface of this system inhibits the initial adhesion of bacteria by the PHEMA hydration outer layer under neutral pH conditions; when bacteria adhere and proliferate on this surface, the bacterially induced acidifification triggers the cleavage of labile amide bonds within the inner layer to expose the positively charged amines and vigorously release melittin (MLT), allowing the surface to timely kill the adhering bacteria. The hierarchical surface employs multiple antibacterial mechanisms to combat bacterial infection and shows high sensitiveness and responsiveness to pathogens. A new paradigm is supplied by this modular hierarchical polymer brushes system for the progress of intelligent surfaces on universal polymer substrates, showing great potential to a promising strategy for preventing infection related to medical devices.