title: Influence of immobilized quaternary ammonium group surface density on antimicrobial efficacy and cytotoxicity.
abstract: Bacterial colonization of medical devices causes infections and is a significant problem in healthcare. The use of antibacterial coatings is considered as a potential solution to this problem and has attracted a great deal of attention. Using concentration density gradients of immobilized quaternary ammonium compounds it was demonstrated that a specific threshold of surface concentration is required to induce significant bacterial death. It was determined that this threshold was 4.18% NR4(+) bonded nitrogen with a surface potential of + 120.4 mV. Furthermore, it is shown for the first time that adhesion of constituents of the culture medium to the quaternary ammonium modified surface eliminated any cytotoxicity towards eukaryotic cells such as primary human fibroblasts. The implications of this type of surface fouling on the antimicrobial efficacy of surface coatings are also discussed.
authors.affiliation: a School of Engineering , University of South Australia , Adelaide, South Australia , Australia.
authors.forename: Alex
authors.initials: A
authors.lastname: Cavallaro
authors.affiliation: b Australian Wine Research Institute , Urrbrae, South Australia , Australia.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Mierczynska
authors.affiliation: c School of Pharmacy and Medical Sciences , University of South Australia , Adelaide, South Australia , Australia.
authors.forename: Mary
authors.initials: M
authors.lastname: Barton
authors.affiliation: a School of Engineering , University of South Australia , Adelaide, South Australia , Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Majewski
authors.affiliation: a School of Engineering , University of South Australia , Adelaide, South Australia , Australia.
authors.forename: Krasimir
authors.initials: K
authors.lastname: Vasilev
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003603:Cytotoxins / Q000494:pharmacology; D004866:Equipment Contamination / Q000517:prevention & control*; D004864:Equipment and Supplies / Q000382:microbiology; D006801:Humans; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*; D013499:Surface Properties / Q000187:drug effects*; D013501:Surface-Active Agents / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D003603:Cytotoxins; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents
keywords: Density gradients; antibacterial; biological fouling; cytotoxicity; quaternary ammonium