Photodynamic Action Mechanism Mediated by of Zinc(II) 2,9,16,23-Tetrakis[4-(N-methylpyridyloxy)]phthalocyanine in Candida albicans Cells

MARÍA ALBANA DI PALMA, ; MARÍA GABRIELA ALVAREZ,; EDGARDO NÉSTOR DURANTINI

PHOTOCHEMISTRY AND PHOTOBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2015 vol. 91 p. 1203 - 1209

0031-8655

The photoreaction type I/type II pathways mediated by zinc (II) 2,9,16,23-tetrakis[4-(N-methylpyridyloxy)]phthalocyanine (ZnPPc4+) was studied in Candida albicans cells. This photosensitizer was strongly bound to C. albicans cells at short times. After 30 min irradiation, 5 lM ZnPPc4+ produced ~5 log decrease in cell viability. Different probes were used to detect reactive oxygen species (ROS) in cell suspensions (~106 CFU mL1). Singlet molecular oxygen, O2(1Dg), wasobserved 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(1Dg). Moreover, the effects produced by an anoxic atmosphere and cell suspensions in D2O, as well as the addition of sodium azide and mannitol as ROS trapping were evaluated in the PDI of C. albicans. These investigation indicates thatO2(1Dg) is generated in the cells, although a minor extension other radical species can also be involved in the PDI of C. albicans mediated by ZnPPc4+.