title: Sterilization effect of atmospheric plasma on Escherichia coli and Bacillus subtilis endospores.
abstract: OBJECTIVE
  Escherichia coli and Bacillus subtilis spores were treated with an atmospheric plasma mixture created by the ionization of helium and oxygen to investigate the inactivation efficiency of a low-temperature plasma below 70 degrees C.
  
  
  RESULTS
  An electrical discharge plasma was produced at a radio frequency (RF) of 13.56 MHz, connected to a perforated circular electrode with a discharge spacing of 1-15 mm. The discharge gas was helium with 0-2% oxygen. For the plasma treatment, a dried E. coli cell or B. subtilis endospore suspension on a cover-glass was exposed to oxygen downstream of the plasma from holes in an RF-powered electrode. The sterilization effect of the RF plasma was highest with 0.2% oxygen, corresponding to the maximum production of oxygen radicals.
  
  
  CONCLUSIONS
  Oxygen radicals generated by RF plasma are effective for the destruction of bacterial cells and endospores.
  
  
  CONCLUSIONS
  Low-temperature atmospheric plasma can be used for the disinfection of diverse objects, especially for the inactivation of bacterial endospores.
authors.affiliation: Department of Molecular Science and Technology, Ajou University, Youngtong-Gu, Suwon, Korea.
authors.forename: Y F
authors.initials: YF
authors.lastname: Hong
authors.forename: J G
authors.initials: JG
authors.lastname: Kang
authors.forename: H Y
authors.initials: HY
authors.lastname: Lee
authors.forename: H S
authors.initials: HS
authors.lastname: Uhm
authors.forename: E
authors.initials: E
authors.lastname: Moon
authors.forename: Y H
authors.initials: YH
authors.lastname: Park
mesh_terms: D000390:Air Ionization; D000391:Air Microbiology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001412:Bacillus subtilis / Q000254:growth & development*; D015169:Colony Count, Microbial; D004560:Electricity; D004926:Escherichia coli / Q000254:growth & development*; D050296:Microbial Viability; D017382:Reactive Oxygen Species / Q000494:pharmacology; D013242:Sterilization / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents; D017382:Reactive Oxygen Species