Título: | STUDY OF THE INTERACTION OF PHTHALOCYANINE-DERIVED PHOTOSENSITIZERS WITH DRUG DELIVERY SYSTEMS FOR PHOTODYNAMIC THERAPY | |||||||
Autor: |
MARIA PAULINA ROMERO OBANDO |
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Colaborador(es): |
SONIA RENAUX WANDERLEY LOURO - Orientador |
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Catalogação: | 10/SET/2012 | Língua(s): | PORTUGUESE - BRAZIL |
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Tipo: | TEXT | Subtipo: | THESIS | |||||
Notas: |
[pt] Todos os dados constantes dos documentos são de inteira responsabilidade de seus autores. Os dados utilizados nas descrições dos documentos estão em conformidade com os sistemas da administração da PUC-Rio. [en] All data contained in the documents are the sole responsibility of the authors. The data used in the descriptions of the documents are in conformity with the systems of the administration of PUC-Rio. |
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Referência(s): |
[pt] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=20323&idi=1 [en] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=20323&idi=2 |
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DOI: | https://doi.org/10.17771/PUCRio.acad.20323 | |||||||
Resumo: | ||||||||
Photodynamic Therapy (PDT) involves irradiation of a tissue with visible
light after application of a photosensitizer. Different reactive species are
produced, which initiate events that result in inactivation or cell death. The
development of photosensitizers and the study of their delivery to sites of the
lesions are important to broaden the applications of PDT. The objective of this
study was to evaluate the properties of phthalocyanines associated with
surfactants that facilitate the distribution and photocatalytic activity of this type of
photosensitizer. The spectroscopic properties of absorption and fluorescence were
used. In a first step, zinc phthalocyanine (ZnPc) was evaluated in formulations
with different ionic (SDS, CTAB, HPS) and nonionic surfactants (Tween 20,
Tween 80, Pluronic F-127 and F-127, Triton X-100). It was found that
concentrated solutions of the surfactants with ZnPc in DMF or DMSO form
unstable nanoemulsions in aqueous solution. At first, ZnPc is monomeric in the
nanoemulsions, but aggregates in the course of time, reducing its efficiency as a
sensitizer. The kinetics of aggregation showed that HPS and CTAB form the more
stable nanoemulsions with aggregation lifetimes greater than two days. Then, a
new menthol phthalocyanine derivative, MentaZnPc, synthesized by K. Oliveira
et al., was evaluated in micelles of the surfactants above, and of several
polyoxyethylenes. The presence of menthol groups as substituents decreased the
stacking tendency and produced a greater solubility in the hydrophobic
compartment of the micelles. Fluorescence, singlet oxygen quantum yields and
photobleaching of the photosensitizers were evaluated in the microheterogeneous
media. The best conditions for 1O2 generation by ZnPc were found in HPS
nanoemulsions. MintZnPc presented an excellent singlet oxygen quantum yield in
non-ionic micelles, especially in Pluronic F-127, which has been widely used in
the pharmaceutical industry.
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