title: Sub-lethal photodynamic inactivation renders Staphylococcus aureus susceptible to silver nanoparticles.
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.
authors.affiliation: Department of Biotechnology, Intercollegiate Faculty of Biotechnology University of Gdansk and Medical University of Gdansk, Gdansk, Poland. strzala@biotech.ug.edu.pl
authors.forename: Joanna
authors.initials: J
authors.lastname: Nakonieczna
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Rapacka-Zdonczyk
authors.forename: Anna
authors.initials: A
authors.lastname: Kawiak
authors.forename: Krzysztof P
authors.initials: KP
authors.lastname: Bielawski
authors.forename: Mariusz
authors.initials: M
authors.lastname: Grinholc
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology*; D011524:Protoporphyrins / Q000494:pharmacology*; D012834:Silver / Q000737:chemistry / Q000494:pharmacology*; D013203:Staphylococcal Infections / Q000188:drug therapy*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000528:radiation effects*
chemical_list: D000900:Anti-Bacterial Agents; D017319:Photosensitizing Agents; D011524:Protoporphyrins; D012834:Silver; C028025:protoporphyrin IX