title: The structures and antibacterial properties of nano-SiO2 supported silver/zinc-silver materials.
abstract: OBJECTIVE
  The aims of this study were to investigate the structures and antibacterial properties of two kinds of sterilizing nano-SiO(2) specimens.
  
  
  METHODS
  The specimens were synthesized by adsorption methodology. One of them was synthesized by adsorbing silver cation onto nano-SiO(2) carrier (silver-loading nano-SiO(2) specimen (SLS)), and the other one by co-adsorbing zinc and silver cations onto the same kind of carrier (zinc-silver-loading nano-SiO(2) specimen (SLZS)). Chemical compositions of these specimens were estimated. The structure and morphology of the specimens were determined by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Also, the antibacterial properties of the specimens were examined.
  
  
  RESULTS
  The amount of silver loaded in SLZS was approximate to that of SLS. Consequently, it can be proved that the amount of nano-SiO(2) adsorbed silver cation did not change with the addition of zinc cation. The obvious differences were not observed among the XRD patterns for each specimen. So it was possible to confirm no formation of new phase(s) after Ag(+)/Zn(2+) absorption. The loaded silver and zinc existed as nano-particles, as observed by HRTEM. Antibacterial properties of SLS and SLZS were excellent against Escherichia coli and S. faecalis. The antibacterial effect of the same antibacterial agent against E. coli or S. faecalis was different. In addition, the antibacterial effect of SLZS was better than that of SLS.
  
  
  CONCLUSIONS
  These results suggested SLS and SLZS can be effectively incorporated in dental resin-based materials to provide antibacterial activity against bacteria.
authors.affiliation: Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China.
authors.forename: Husheng
authors.initials: H
authors.lastname: Jia
authors.forename: Wensheng
authors.initials: W
authors.lastname: Hou
authors.forename: Liqiao
authors.initials: L
authors.lastname: Wei
authors.forename: Bingshe
authors.initials: B
authors.lastname: Xu
authors.forename: Xuguang
authors.initials: X
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D003764:Dental Materials / Q000737:chemistry; D004337:Drug Carriers; D013293:Enterococcus faecalis / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D006801:Humans; D008422:Materials Testing; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D012822:Silicon Dioxide / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D012834:Silver / Q000737:chemistry* / Q000494:pharmacology; D013499:Surface Properties; D014961:X-Ray Diffraction; D015032:Zinc / Q000737:chemistry* / Q000494:pharmacology