title: Photocatalytic bactericidal action of fluorescent light in a titanium dioxide particle mixture: an in vitro study.
abstract: Traditional titanium dioxide (TiO(2)) has photocatalytic bactericidal properties only under ultraviolet (UV) irradiation, which restricts its use in clinical treatment regimens. In this study, we evaluated the photocatalytic bactericidal effects of an aqueous system of TiO(2) particles irradiated by fluorescent light (FL) on Staphylococcus aureus. A TiO(2) particle mixture containing 19 ppm (0.019 mg/mL) of TiO(2) was prepared. A bacterial solution of 1 x 10(5) CFU/mL was added one drop at a time to the TiO(2) mixture. The resulting product was then irradiated with FL. The bacterial survival rate decreased steadily in the TiO(2) mixture group, reaching 76.7% after 30 min of FL irradiation and 10.9% after 60 min. After 60 to 180 min, the bacterial survival ratio of the TiO(2) mixture group was significantly lower than that of the control group (P < 0.05). The present study indicates that treating the surfaces of surgical devices and the surgical field with a TiO(2) particle mixture can create a nearly sterile environment that can be maintained throughout surgery, even at low luminous intensities.
authors: Department of Orthopedic Surgery, Graduate School of Biomedical Science, Nagasaki University, Nagasaki, Japan. f2101@cc.nagasaki-u.ac.jp
authors: Hironobu
authors: H
authors: Koseki
authors: Koutaro
authors: K
authors: Shiraishi
authors: Tomohiko
authors: T
authors: Asahara
authors: Toshiyuki
authors: T
authors: Tsurumoto
authors: Hiroyuki
authors: H
authors: Shindo
authors: Koumei
authors: K
authors: Baba
authors: Hiroshi
authors: H
authors: Taoda
authors: Nao
authors: N
authors: Terasaki
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002384:Catalysis; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D015169:Colony Count, Microbial; D005453:Fluorescence; D006801:Humans; D008027:Light; D008422:Materials Testing; D013211:Staphylococcus aureus / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry / Q000528:radiation effects
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; C009495:titanium dioxide; D014025:Titanium