title: Photophysical and photobiological studies of a silicon tribenzonaphthoporphyrazinato incorporated into liposomes for photodynamic therapy use.
abstract: Nanostructured drug delivery systems (NDDS), such as liposomes, represent a growing area in biomedical research. These microheterogeneous media can be used in many biological systems to provide appropriate drug levels with a specific biodistribution. The photophysical properties of a silicon derivative of tribenzonaphthoporphyrazinato (Si-tri-PcNc) incorporated into liposome were studied by steady-state techniques, time-resolved fluorescence and laser flash photolysis. All the spectroscopy measurements performed allowed us to conclude that Si-tri-PcNc in liposome is a promising NDDS for PDT. The in vitro experiments with liposomal NDDS showed that the system is not cytotoxic in darkness, but exhibits a substantial phototoxicity at 1 microM of photosensitizer concentration and 10.0 J/cm2 of light. These conditions are sufficient to kill about 80% of the cells.
authors.affiliation: Departamento de Química, Laboratório de Fotobiologia e Fotomedicina, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
authors.forename: Andreza R
authors.initials: AR
authors.lastname: Simioni
authors.forename: Marcelo M M
authors.initials: MM
authors.lastname: Pelisson
authors.forename: Milton
authors.initials: M
authors.lastname: Beltrame
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Tedesco
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D008081:Liposomes; D051379:Mice; D017646:Organosilicon Compounds / Q000737:chemistry*; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D008081:Liposomes; D017646:Organosilicon Compounds; D017319:Photosensitizing Agents; C517915:silicon tribenzonaphthoporphyrazate