New insights into the bactericidal activity of chitosan-Ag bionanocomposite: the role of the electrical conductivity

Colloids Surf B Biointerfaces. 2013 Nov 1:111:741-6. doi: 10.1016/j.colsurfb.2013.07.003. Epub 2013 Jul 10.

Abstract

The relationship between electrical conductivity, structure and antibacterial properties of chitosan-silver nanoparticles (CS/AgnP) biocomposites has been analyzed. To test the film's antimicrobial activity, Gram-positive and Gram-negative bacteria were studied. The interactions between silver nanoparticles with chitosan suggest the formation of silver ions which plays a major role in nanocomposite's bactericidal potency. In CS/AgnP biocomposites, the bactericide effectiveness increases by increasing AgnP concentrations up to 3 wt%, which is close to the electrical percolation threshold of ca. 3 wt%. As the AgnP concentration increases above this threshold, the bactericidal potency is greatly diminished. The elucidated correlation between electrical conductivity and antibacterial activity could be useful in the design of other nanocomposites that involve polymeric-based matrices.

Keywords: Bactericide; Chitosan; Electrical conductivity; Percolation threshold; Silver nanoparticles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacteria / drug effects
  • Chitosan / pharmacology*
  • Electric Conductivity*
  • Microbial Sensitivity Tests
  • Nanocomposites / ultrastructure
  • Photoelectron Spectroscopy
  • Silver / pharmacology*
  • Spectroscopy, Fourier Transform Infrared

Substances

  • Anti-Bacterial Agents
  • Silver
  • Chitosan