title: Bioinspired and biocompatible carbon nanotube-Ag nanohybrid coatings for robust antibacterial applications.
abstract: The design of self-sterilizing surfaces with favorable biocompatibility is acknowledged as an effective approach to deal with the bacterial infections of biomedical devices. In this study, we report an intriguing protocol for the large-scale fabrication of self-sterilizing and biocompatible surface film coatings by using polymer shielded silver nanoparticle loaded oxidized carbon nanotube (AgNPs@oCNT) nano-dispersions. To achieve the antibacterial coatings, the bioinspired positively charged and negatively charged AgNPs@oCNTs were alternately deposited onto substrates by spray-coating assisted layer-by-layer assembly. Then the bacterial inhibitory zones, optical density value monitoring, bacterial killing efficiency and adhesion were investigated; and all the results revealed that the AgNPs@oCNTs thin film coatings exhibited robust and long-term antibacterial activity against both Gram negative and Gram positive bacteria. Moreover, due to the shielding effects of polymer layers, the coatings showed extraordinary blood compatibility and limited toxicity against human umbilical vein endothelial cells. It is believed that the proposed large-scale fabrication of bactericidal, blood and cell compatible AgNPs@oCNT based thin film coatings will have great potential to forward novel operational pathogenic inhibition strategies to avoid undesired bacterial contaminations of biomedical implants or biological devices.
  
  
  
  Bacterial infection of medical devices has been considered to be a world-wide clinical threat towards patients' health. In this study, a bioinspired and biocompatible antibacterial coating was prepared via the spray-assisted layer-by-layer (LbL) assembly. The silver nanopartilces loaded oxidized carbon nanotube (AgNPs@oCNT), which were coated by functional polymers (chitosan and synthetic heparin mimicking polymers), were prepared via mussel inspired chemistry; and the spray-assisted assembly process allowed the fast construction on devices. Owing to the antibacterial efficiency of the loaded AgNPs, the coating showed robust bacterial killing activity and resistance towards bacterial adhesion. Moreover, since that the AgNPs were shielded by the polymers, the coating exhibited no clear toxicity at blood or cellular level. Benefiting from the universal and large-scale fabrication advancements of the spray assisted LbL coating; it is believed that the proposed strategy can be applied in designing many other kinds of self-sterilizing biomedical implants and devices.
authors.affiliation: College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
authors.forename: Chuanxiong
authors.initials: C
authors.lastname: Nie
authors.affiliation: College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Yang
authors.affiliation: College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China; Department of Chemistry and Biochemistry, Freie Universitat Berlin, Takustr. 3, 14195 Berlin, Germany. Electronic address: sagecheng@163.com.
authors.forename: Chong
authors.initials: C
authors.lastname: Cheng
authors.affiliation: College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
authors.forename: Lang
authors.initials: L
authors.lastname: Ma
authors.affiliation: College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Deng
authors.affiliation: Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huaian 223003, China.
authors.forename: Lingren
authors.initials: L
authors.lastname: Wang
authors.affiliation: College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China; National Engineering Research Center for Biomaterials, Sichuan University, Chengdu 610064, China. Electronic address: zhaochsh70@163.com.
authors.forename: Changsheng
authors.initials: C
authors.lastname: Zhao
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D040761:Biomimetic Materials / Q000737:chemistry*; D002448:Cell Adhesion / Q000187:drug effects; D016923:Cell Death / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004926:Escherichia coli / Q000187:drug effects; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects; D006801:Humans; D008297:Male; D008422:Materials Testing; D008826:Microbial Sensitivity Tests; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D056951:Photoelectron Spectroscopy; D010973:Platelet Adhesiveness / Q000187:drug effects; D012834:Silver / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D037742:Nanotubes, Carbon; D014867:Water; D012834:Silver
keywords: Ag-carbon nanotube composites; Antibacterial biomaterials; Bactericidal activity; Blood and cell compatibility; Layer-by-layer spray-coating