In vitro phototoxicity of new quinolones: production of active oxygen species and photosensitized lipid peroxidation

Photodermatol Photoimmunol Photomed. 1999 Dec;15(6):226-30. doi: 10.1111/j.1600-0781.1999.tb00094.x.


To elucidate photosensitization potentials of new quinolone antibacterial agents, production of active oxygen species and peroxidation of squalene after ultraviolet A exposure were investigated. Production of singlet oxygen and/or hydrogen peroxide was estimated by bleaching of p-nitroso-N,N-dimethylaniline. Lomefloxacin showed the greatest ability to produce active oxygen species, and this ability was reduced by the addition of the singlet oxygen quencher sodium azide. Ciprofloxacin and fleroxacin also had strong activity. Photosensitized peroxidation of squalene was evaluated by measurement of thiobarbituric acid-reactive substances. Lomefloxacin was the strongest sensitizer, followed by fleroxacin and ciprofloxacin. These results suggest that certain new quinolones are involved in phototoxicity via the mechanism of active oxygen species.

MeSH terms

  • Anti-Infective Agents / chemistry*
  • Ciprofloxacin / chemistry
  • DNA Damage*
  • Dermatitis, Phototoxic*
  • Fleroxacin / chemistry
  • Fluoroquinolones*
  • Humans
  • Lipid Peroxidation / radiation effects*
  • Norfloxacin / chemistry
  • Ofloxacin / chemistry
  • Quinolones / chemistry
  • Reactive Oxygen Species / metabolism*
  • Squalene / radiation effects
  • Time Factors
  • Ultraviolet Rays


  • Anti-Infective Agents
  • Fluoroquinolones
  • Quinolones
  • Reactive Oxygen Species
  • Ciprofloxacin
  • Squalene
  • Ofloxacin
  • lomefloxacin
  • Norfloxacin
  • Fleroxacin