title: Synergetic inactivation of Staphylococcus epidermidis and Streptococcus mutansin a TiO2/H2O2/UV system.
abstract: TiO 2 photocatalysis can be used to kill surface adherent bacteria on biomaterials, and is particularly interesting for use with percutaneous implants and devices. Its efficiency and safety, however, depend on the activation energy required. This in vitro study investigates synergetic effects against the clinically relevant strains S. epidermidis and S. mutans when combining photocatalytic surfaces with H2O2. After 20 min exposure to 0.1 wt% H2O2 and UV light on TiO2 surfaces, viabilities of S. epidermidis and S. mutans were reduced by 99.7% and 98.9%, respectively. Without H2O2 the corresponding viability reduction was 86% for S. epidermidis and 65% for S. mutans. This study indicates that low concentrations of H2O2 can enhance the efficiency of photocatalytic TiO2 surfaces, which could potentially improve current techniques used for decontamination and debridement of TiO2 coated biomedical implants and devices.
authors.affiliation: Division of Applied Materials Science; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Unosson
authors.affiliation: Division of Nanotechnology and Functional Materials; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden.
authors.forename: Eleni K
authors.initials: EK
authors.lastname: Tsekoura
authors.affiliation: Division of Applied Materials Science; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden.
authors.forename: Håkan
authors.initials: H
authors.lastname: Engqvist
authors.affiliation: Division of Nanotechnology and Functional Materials; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden.
authors.forename: Ken
authors.initials: K
authors.lastname: Welch
mesh_terms: D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000494:pharmacology; D004203:Disinfection / Q000379:methods*; D004357:Drug Synergism; D006861:Hydrogen Peroxide / Q000737:chemistry* / Q000494:pharmacology*; D008422:Materials Testing; D050296:Microbial Viability / Q000187:drug effects / Q000528:radiation effects; D013212:Staphylococcus epidermidis / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D013295:Streptococcus mutans / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D020099:Coated Materials, Biocompatible; C009495:titanium dioxide; D006861:Hydrogen Peroxide; D014025:Titanium
keywords: UV light; antibacterial; hydrogen peroxide; photocatalysis; photolysis; synergy; titanium dioxide