Sub-lethal photodynamic inactivation renders Staphylococcus aureus susceptible to silver nanoparticles

Photochem Photobiol Sci. 2013 Sep;12(9):1622-7. doi: 10.1039/c3pp50039j. Epub 2013 May 28.

Abstract

Staphylococcus aureus is a common etiological factor in infections of burns and other chronic wounds. The development of an effective and fast-acting treatment would be enormously beneficial and is highly desired. We focused on testing the bactericidal efficacy of photoinactivation using a known photosensitizer (protoporphyrin IX, PPIX) in sequential combination with silver nanoparticles against S. aureus. Using PPIX-based photoinactivation followed by silver nanoparticles we obtained a high bactericidal effect (7 log10 units reduction) with limited harmful effects on human epidermal keratinocytes. Moreover, we observed that the use of silver nanoparticles prevents bacterial re-growth 24 h post-PDI treatment. A sequential combination of photoinactivation and silver nanoparticles represents a potentially effective antibacterial approach.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Cell Line
  • Humans
  • Nanoparticles / chemistry
  • Photochemotherapy
  • Photosensitizing Agents / pharmacology*
  • Protoporphyrins / pharmacology*
  • Silver / chemistry
  • Silver / pharmacology*
  • Staphylococcal Infections / drug therapy*
  • Staphylococcus aureus / drug effects*
  • Staphylococcus aureus / radiation effects*

Substances

  • Anti-Bacterial Agents
  • Photosensitizing Agents
  • Protoporphyrins
  • Silver
  • protoporphyrin IX