Título principal
Redes Neurais Artificiais Aplicadas ao Controle de um Retificador Buck PFC Monofásico [recurso eletrônico] / Carlúcio Pereira da Silva ; orientador, Diego Santos Greff
Data de publicação
2024
Descrição física
130 p. : il.
Nota
Disponível somente em versão on-line.
Dissertação (mestrado) – Universidade Federal de Santa Catarina, Centro Tecnológico de Joinville, Programa de Pós-Graduação em Engenharia de Sistemas Eletrônicos, Florianópolis, 2024.
Inclui referências.
Redes Neurais Artificiais Aplicadas ao Controle de um Retificador Buck PFC Monofásico [recurso eletrônico] / Carlúcio Pereira da Silva ; orientador, Diego Santos Greff
Data de publicação
2024
Descrição física
130 p. : il.
Nota
Disponível somente em versão on-line.
Dissertação (mestrado) – Universidade Federal de Santa Catarina, Centro Tecnológico de Joinville, Programa de Pós-Graduação em Engenharia de Sistemas Eletrônicos, Florianópolis, 2024.
Inclui referências.
Abstract: Abstract: Recent advances in the development of nanomaterials have allowed their application in the controlled release of drugs for local treatment against cancer. However, despite the numerous systems reported in this area, the accumulation low rate of the nanomaterials in the biological systems remains a challenge. Polymeric nanoparticles (Nps) homogeneously distributed in polymer nanofibers (Nfs) formed by eletrospinning are an alternative to overcome these challenges. Thus, in this doctoral theses, a new nanomaterial was developed by dispersion of the Nps of carboxymethyl hexanoyl chitosan/dodecyl sulfate (CHQ-SDS) in PEO/chitosan Nfs (PEOCh-H3). The nanomaterial was applied in the controlled release of pyrazoline (H3TM04), which have activity against leukemia and melanoma cancer cells. The thesis was developed in 3 stages: i) A fundamental study, to understand the interaction process and nanoaggregates formation of the carboxymethyl hexanoyl chitosan / dodecyl sulfate. ii) Formation of CHQ-SDS Nps applied in the encapsulation and in vitro assays against leukemic cells. iii) The formation of the Nfs PEOCh-H3 by eletrospinning, and applied in vitro and ex vivo release of H3TM04 in melanoma cells and human skin. The formation of CHQ-SDS nanoaggregates occurs by hydrophobic assembly between the SDS and CHQ, where this is a thermodynamically favorable process. On the other hand, the presence of SDS decreases the hydrodynamic radius and surface charge of the nanoaggregates, increasing the colloidal stability in aqueous solution for up to 150 days. The CHQ-SDS Nps were formed at pH 7.4 and characterized by dynamic light scattering, electron transmission microscopy and zeta potential, showed a spherical morphology. The encapsulation efficiency of H3TM04 was 96% and the nanoparticles had 83,9 ± 1,2 nm of the hydrodynamic radius. The in vitro release results demonstrated that the active compound release process occurs by the Nps erosion, decreasing the inhibitory concentration (IC50) for leukemia cells (Jukat and K-562). Finally, the PEOCh-H3 nanofibers were formed and characterized by thermal and microscopic techniques. The Nps were evidenced within the Nfs by transmission electron microscopy. in vitro studies demonstrated that the release process of H3TM04 occurs by diffusion and erosion of the nanomaterial during 120 h. On the other hand, PEOCh-H3 increases the accumulation of the active compounds in the epidermis (ex vivo release test on human skin), as well as increases the cytotoxic effect of H3TM04 in melanoma cells (in vitro test). This double release barrier (Nfs/Nps) is a promising candidate for the controlled release of drugs to increases the accumulation rate of the active compound in the biological tissue.