title: Silver against Pseudomonas aeruginosa biofilms.
abstract: Silver has been recognized for its antimicrobial properties for centuries. Most studies on the antibacterial efficacy of silver, with particular emphasis on wound healing, have been performed on planktonic bacteria. Our recent studies, however, strongly suggest that colonization of wounds involves bacteria in both the planktonic and biofilm modes of growth. The action of silver on mature in vitro biofilms of Pseudomonas aeruginosa, a primary pathogen of chronic infected wounds, was investigated. The results show that silver is very effective against mature biofilms of P. aeruginosa, but that the silver concentration is important. A concentration of 5-10 mug/mL silver sulfadiazine eradicated the biofilm whereas a lower concentration (1 mug/mL) had no effect. The bactericidal concentration of silver required to eradicate the bacterial biofilm was 10-100 times higher than that used to eradicate planktonic bacteria. These observations strongly indicate that the concentration of silver in currently available wound dressings is much too low for treatment of chronic biofilm wounds. It is suggested that clinicians and manufacturers of the said wound dressings consider whether they are treating wounds primarily colonized either by biofilm-forming or planktonic bacteria.
authors: BioScience & Technology, BioCentrum, Technical University of Denmark, Lyngby, Denmark.
authors: Thomas
authors: T
authors: Bjarnsholt
authors: Klaus
authors: K
authors: Kirketerp-Møller
authors: Søren
authors: S
authors: Kristiansen
authors: Richard
authors: R
authors: Phipps
authors: Anne Kirstine
authors: AK
authors: Nielsen
authors: Peter Østrup
authors: PØ
authors: Jensen
authors: Niels
authors: N
authors: Høiby
authors: Michael
authors: M
authors: Givskov
mesh_terms: D018441:Biofilms / Q000187:drug effects*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000502:physiology; D053038:Quorum Sensing; D012834:Silver / Q000494:pharmacology*; D012837:Silver Sulfadiazine / Q000494:pharmacology
chemical_list: D012834:Silver; D012837:Silver Sulfadiazine