title: Differential sensitivity of osteoblasts and bacterial pathogens to 405-nm light highlighting potential for decontamination applications in orthopedic surgery.
abstract: Healthcare associated infections pose a major threat to patients admitted to hospitals and infection rates following orthopedic arthroplasty surgery are as high as 4%. A 405-nm high-intensity narrow spectrum light has been proven to reduce environmental contamination in hospital isolation rooms, and there is potential to develop this technology for application in arthroplasty surgery. Cultured rat osteoblasts were exposed to varying light intensities and it was found that exposures of up to a dose of 36 J/cm2 had no significant effect on cell viability [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay], function (alkaline phosphatase activity), and proliferation rate (BrdU cell proliferation assay). High irradiance exposures (54 J/cm2) significantly affected the cell viability indicating that the effects of 405-nm light on osteoblasts are dose dependent. Additionally, exposure of a variety of clinically related bacteria to a dose of 36 J/cm2 resulted in up to 100% kill. These results demonstrating the differential sensitivity of osteoblasts and bacteria to 405-nm light are an essential step toward developing the technique for decontamination in orthopedic surgery.
authors.affiliation: University of Strathclyde, Department of Biomedical Engineering, Wolfson Centre, 106 Rottenrow, Glasgow, Scotland G4 0NW, United Kingdom.
authors.forename: Praveen
authors.initials: P
authors.lastname: Ramakrishnan
authors.affiliation: University of Strathclyde, The Robertson Trust Laboratory for Electronic Sterilisation Technologies, 204 George Street, Glasgow, Scotland G1 1XW, United Kingdom.
authors.forename: Michelle
authors.initials: M
authors.lastname: Maclean
authors.affiliation: University of Strathclyde, The Robertson Trust Laboratory for Electronic Sterilisation Technologies, 204 George Street, Glasgow, Scotland G1 1XW, United Kingdom.
authors.forename: Scott J
authors.initials: SJ
authors.lastname: MacGregor
authors.affiliation: University of Strathclyde, The Robertson Trust Laboratory for Electronic Sterilisation Technologies, 204 George Street, Glasgow, Scotland G1 1XW, United Kingdom.
authors.forename: John G
authors.initials: JG
authors.lastname: Anderson
authors.affiliation: University of Strathclyde, Department of Biomedical Engineering, Wolfson Centre, 106 Rottenrow, Glasgow, Scotland G4 0NW, United Kingdom.
authors.forename: M Helen
authors.initials: MH
authors.lastname: Grant
mesh_terms: D000818:Animals; D001419:Bacteria / Q000528:radiation effects*; D002461:Cell Line, Transformed; D049109:Cell Proliferation / Q000528:radiation effects; D048430:Cell Shape / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects*; D004203:Disinfection / Q000379:methods*; D006801:Humans; D008027:Light; D050296:Microbial Viability / Q000528:radiation effects*; D019637:Orthopedic Procedures; D010006:Osteoblasts / Q000528:radiation effects*; D051381:Rats