• 文献标题:   Enhanced Photothermal Bactericidal Activity of the Reduced Graphene Oxide Modified by Cationic Water-Soluble Conjugated Polymer
  • 文献类型:   Article
  • 作  者:   XIAO LH, SUN JH, LIU LB, HU R, LU H, CHENG CG, HUANG Y, WANG S, GENG JX
  • 作者关键词:   graphene, watersoluble conjugated polymer, covalent functionalization, electrostatic attraction, photothermal killing of bacteria
  • 出版物名称:   ACS APPLIED MATERIALS INTERFACES
  • ISSN:   1944-8244
  • 通讯作者地址:   Chinese Acad Sci
  • 被引频次:   25
  • DOI:   10.1021/acsami.6b14473
  • 出版年:   2017

▎ 摘  要

Surface modification of graphene is extremely important for applications. Here, we report a grafting-through method for grafting water-soluble polythiophenes onto reduced graphene oxide (RGO) sheets. As a result of tailoring of the side chains of the polythiophenes, the modified RGO sheets, that is, RGO-g-P3TOPA and RGO-g-P3TOPS, are positively and negatively charged, respectively. The grafted water-soluble polythiophenes provide the modified RGO sheets with good dispersibility in water and high photothermal conversion efficiencies (ca. 88%). Notably, the positively charged RGO-g-P3TOPA exhibits unprecedentedly excellent photothermal bactericidal activity, because the electrostatic attractions between RGO-g-P3TOPA and Escherichia coli (E. coli) bind them together, facilitating direct heat conduction through their interfaces: the minimum concentration of RGO-g-P3TOPA that kills 100% of E. coli is 2.5 mu g mL(-1), which is only 1/16th of that required for RGO-g-P3TOPS to exhibit a similar bactericidal activity. The direct heat conduction mechanism is supported by zeta-potential measurements and photothermal heating tests, in which the achieved temperature of the RGO-g-P3TOPA suspension (2.5 mu g mL(-1), 32 degrees C) that kills 100% of E. coli is found to be much lower than the thermoablation threshold of bacteria. Therefore, this research demonstrates a novel and superior method that combines photothermal heating effect and electrostatic attractions to efficiently kill bacteria.