Antibacterial and antifouling activities of chitosan/TiO2/Ag NPs nanocomposite films against packaged drinking water bacterial isolates

Environ Sci Pollut Res Int. 2016 Oct;23(19):19529-40. doi: 10.1007/s11356-016-7102-6. Epub 2016 Jul 7.

Abstract

TiO2 and Ag NPs are widely used as antibacterial agents against many bacterial pathogens. Chitosan (polymer) itself acts as a strong antibacterial agent. Hence, chitosan/TiO2/Ag NPs incorporated nanocomposite film was prepared against packed drinking water bacterial strains. A concentration-dependent increase in the reduction of cell viability was observed in all the isolates under UV-C and dark exposure conditions. The bacteria consortium showed greater resistance against antibacterial effects of chitosan/TiO2/Ag nanocomposite as compared to single isolates. Glycocalyx test and mass assessment conclude the effective antibacterial activity by inhibiting bacterial adhesion on the film surface. The release of LDH and generation of ROS act as the predominant antibacterial mechanism induced by TiO2/Ag NPs. Surface characterization of chitosan/TiO2/Ag nanocomposite was studied by FTIR and XRD analyses and SEM analysis after interaction with the bacteria.

Keywords: Antibacterial activity; Chitosan/TiO2/Ag nanocomposite; Consortium; Dark; UV-C.

MeSH terms

  • Anti-Bacterial Agents / toxicity*
  • Bacteria / drug effects
  • Chitosan / toxicity*
  • Drinking Water / chemistry
  • Drinking Water / microbiology*
  • Nanocomposites / toxicity*
  • Polymers
  • Silver / toxicity*
  • Titanium / toxicity*
  • Water Purification / methods*

Substances

  • Anti-Bacterial Agents
  • Drinking Water
  • Polymers
  • titanium dioxide
  • Silver
  • Chitosan
  • Titanium