title: A sterilization system using ultraviolet photochemical reactions based on nitrous oxide and oxygen gases.
abstract: Active oxygen species (AOS) generated under ultraviolet (UV) lamps can be applied for various industrial processes owing to extremely strong oxidative abilities. We have already reported on an application of the AOS for a sterilization process of microorganisms. Here, a sterilization method using active oxygen generated under ultraviolet (UV) lamps introducing nitrous oxide (N2O) and oxygen gases into a vacuum chamber was investigated. Nitrogen dioxide (NO2) gas was readily produced from N2O by UV photochemical reactions under the low-pressure mercury lamp and then used to sterilize medical devices. We compared the ability of the N2O gas to sterilize Geobacillus stearothermophilus spores with those of conventional methods. Successful sterilization of spores on various biological indicators was achieved within 60 min, not only in sterilization bags but also in a lumen device.
authors.affiliation: Tokai University, 4-1-1, Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Ohnishi
authors.affiliation: Tokai University, 4-1-1, Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan; Iwasaki Electric Co., Ltd., 1-1, Ichiriyama-cho, Gyoda City, Saitama 361-8505, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsumoto
authors.affiliation: Tokai University, 4-1-1, Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan. Electronic address: iwamori@tokai-u.jp.
authors.forename: Satoru
authors.initials: S
authors.lastname: Iwamori
mesh_terms: D015169:Colony Count, Microbial; D001411:Geobacillus stearothermophilus / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects; D007202:Indicators and Reagents / Q000737:chemistry; D050296:Microbial Viability / Q000187:drug effects / Q000528:radiation effects; D009609:Nitrous Oxide / Q000737:chemistry; D055668:Photochemical Processes; D017382:Reactive Oxygen Species / Q000737:chemistry*; D013171:Spores, Bacterial / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects; D013242:Sterilization / Q000295:instrumentation / Q000379:methods*; D014466:Ultraviolet Rays; D014618:Vacuum
chemical_list: D007202:Indicators and Reagents; D017382:Reactive Oxygen Species; D009609:Nitrous Oxide
keywords: Active oxygen sterilization; Geobacillus stearothermophilus spores; Lumen device; Nitrous oxide (N(2)O); Ultraviolet (UV) lamp