title: Photodynamic Action Mechanism Mediated by Zinc(II) 2,9,16,23-Tetrakis[4-(N-methylpyridyloxy)]phthalocyanine in Candida albicans Cells.
abstract: The photoreaction type I/type II pathways mediated by zinc(II) 2,9,16,23-tetrakis[4-(N-methylpyridyloxy)]phthalocyanine (ZnPPc(4+) ) was studied in Candida albicans cells. This photosensitizer was strongly bound to C. albicans cells at short times. After 30 min irradiation, 5 μM ZnPPc(4+) produced ~5 log decrease in cell viability. Different probes were used to detect reactive oxygen species (ROS) in cell suspensions (~10(6) CFU mL(-1) ). Singlet molecular oxygen, O2 ((1) Δg ), was observed by the reaction with 9,10-dimethylanthracene (DMA) and tetrasodium 2,2-(anthracene-9,10-diyl)bis(methylmalonate) (ABMM), whereas the nitro blue tetrazolium (NBT) method was used to sense superoxide anion radical (O2·-). Moreover, the effects produced by an anoxic atmosphere and cell suspensions in D2 O, as well as the addition of sodium azide and mannitol as ROS trapping were evaluated in the PDI of C. albicans. These investigation indicates that O2 ((1) Δg ) is generated in the cells, although a minor extension other radical species can also be involved in the PDI of C. albicans mediated by ZnPPc(4+) .
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.
authors.forename: María Albana
authors.initials: MA
authors.lastname: Di Palma
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.
authors.forename: María Gabriela
authors.initials: MG
authors.lastname: Alvarez
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.
authors.forename: Edgardo N
authors.initials: EN
authors.lastname: Durantini
mesh_terms: D002176:Candida albicans / Q000187:drug effects* / Q000528:radiation effects*; D056831:Coordination Complexes / Q000737:chemistry* / Q000494:pharmacology; D017319:Photosensitizing Agents / Q000737:chemistry / Q000494:pharmacology; D026082:Singlet Oxygen / Q000737:chemistry; D015032:Zinc / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D017319:Photosensitizing Agents; C000608704:zinc(II) 2,9,16,23-tetrakis(4-(N-methylpyridyloxy))phthalocyanine; D026082:Singlet Oxygen; D015032:Zinc