title: Photodynamic inactivation of Candida albicans by BAM-SiPc.
abstract: Photodynamic therapy is a treatment that combines the use of three non-toxic components, viz. photosensitiser, light and oxygen to cause localised oxidative photodamage. In the present study, the antifungal effect of the photosensitiser, BAM-SiPc, an unsymmetrical bisamino phthalocyanine, was investigated. BAM-SiPc was effective in photo-inactivating Candida albicans in a dose-dependent manner. The cell viability as determined by the clonogenic assay was reduced to c. 10% at 0.02 micromol l(-1) BAM-SiPc with a total fluence of 12 J cm(-2) at a cell density of 10(7) cells ml(-1). A short incubation time of 5-15 min was sufficient to allow the photosensitiser to exert its optimal antifungal activity. Microscopical analysis showed that BAM-SiPc was effectively internalised by the fungal cells. Photodynamic treatment led to an increase in the intracellular reactive oxygen species level and disturbed the membrane integrity of the fungal cells.
authors.affiliation: Department of Biochemistry, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Cheung-Wai
authors.initials: CW
authors.lastname: So
authors.forename: Paul W K
authors.initials: PW
authors.lastname: Tsang
authors.forename: Pui-Chi
authors.initials: PC
authors.lastname: Lo
authors.forename: C J
authors.initials: CJ
authors.lastname: Seneviratne
authors.forename: Lakshman P
authors.initials: LP
authors.lastname: Samaranayake
authors.forename: Wing-Ping
authors.initials: WP
authors.lastname: Fong
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D002176:Candida albicans / Q000737:chemistry / Q000187:drug effects*; D002462:Cell Membrane / Q000187:drug effects; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D050296:Microbial Viability / Q000187:drug effects; D015394:Molecular Structure; D017646:Organosilicon Compounds / Q000494:pharmacology*; D017319:Photosensitizing Agents / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000032:analysis; D013997:Time Factors
chemical_list: D000935:Antifungal Agents; C516359:BAM-SiPc; D007211:Indoles; D017646:Organosilicon Compounds; D017319:Photosensitizing Agents; D017382:Reactive Oxygen Species