Skip to Content
MilliporeSigma
  • In vitro photodynamic inactivation of Cryptococcus neoformans melanized cells with chloroaluminum phthalocyanine nanoemulsion.

In vitro photodynamic inactivation of Cryptococcus neoformans melanized cells with chloroaluminum phthalocyanine nanoemulsion.

Photochemistry and photobiology (2011-12-08)
Gabriela B Rodrigues, Fernando L Primo, Antonio C Tedesco, Gilberto U L Braga
ABSTRACT

The selection of fungi resistant to currently used fungicides and the emergence of new pathogenic species make the development of alternative fungus-control techniques highly desirable. Photodynamic antimicrobial chemotherapy (PACT) is a promising method which combines a nontoxic photosensitizer (PS) with visible light to cause selective killing of microbial cells. The development of PACT to treat mycoses or kill fungi in the environment depends on identifying effective PS for the different pathogenic species and delivery systems able to expand and optimize their use. In the present study, the in vitro susceptibility of Cryptococcus neoformans melanized cells to the photodynamic effects of the PS agent ClAlPc in nanoemulsion (ClAlPc/NE) was examined. Cells were killed in a PS concentration- and light dose-dependent manner. Treatment with ClAlPc/NE, using PS concentrations (e.g. 4.5 μm) and light doses (e.g. 10 J cm(-2)) compatible with PACT, resulted in a reduction of up to 6 logs in survival. Washing the cells to remove unbound PS before light exposure did not inhibit fungal photodynamic inactivation. Internalization of ClAlPc by C. neoformans was confirmed by confocal fluorescence microscopy, and the degree of uptake was dependent on PS concentration.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Aluminum phthalocyanine chloride, Dye content ~85 %