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Photophysical and photobiological studies of drug delivery systems loaded with chloro-aluminium phthalocyanine for application in photodynamic therapy

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Emanoel Pedro de Oliveira Silva
Total Authors: 1
Document type: Doctoral Thesis
Press: Ribeirão Preto.
Institution: Universidade de São Paulo (USP). Faculdade de Ciências Farmacêuticas de Ribeirão Preto (PCARP/BC)
Defense date:
Examining board members:
Priscyla Daniely Marcato Gaspari; Fernando Lucas Primo
Advisor: Antonio Claudio Tedesco

The Photodynamic therapy (PDT) has been an alternative for the treatment of skin, and brain tumors, and has shown promising results, both in vitro and in vivo, is a simple and non-evasive technique. The therapy consists into a light-sensitive drug excitation by a light visible source that once absorbed by the molecule lead to produce reactive oxygen species (ROS) in the molecular oxygen presence by a sequence of photochemical reactions. This work proposes the preparation and characterization of a cholesterol-rich nanoemulsion and ultradeformable liposomes as new delivery systems for the drug photosensitizer chloro aluminum phthalocyanine (PcAlCl) compared to a classical system as the conventional liposome and their photodynamic activity in glioblastoma cells line (U87MG) and melanoma cells line (B16F10). The formulations showed suitable characteristics such as reproducibility, particle size, short and long-term stability and deformity for their use as drug delivery for PcAlCl. For the photophysical studies: absorption, fluorescence, fluorescence quantum yield (?F), fluorescence lifetime (?) and quantum yield of singlet oxygen (??) of PcAlCl in ethanol and incorporated in the formulations demonstrated that the incorporation was able to improve its photophysical characteristics. In in vitro studies, the drug delivery systems showed no cytotoxicity in the absence of light, but demonstrated increased in PcAlCl photodynamic activity up to 80% over the PcAlCl free when irradiated. All formulations showed characteristics, which cooperates with the use of these drug delivery systems for, increased the PcAlCl photodynamic activity for glioblastoma and melanoma treatment (AU)

FAPESP's process: 12/25216-3 - Photophysical and photobiological studies of drug delivery systems for photosensitizer application in photodynamic therapy
Grantee:Emanoel Pedro de Oliveira Silva
Support type: Scholarships in Brazil - Doctorate