SOUZA, E.F. Development of pH-and temperature-sensitive microgel particles: synthesis monitoring, characterisation and application as potential oral drug carriers. Versão corrigida. 2019. 221 p. Tese (Doutorado

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The porosity of hydrogels is a parameter of great importance for biomedical applications. Techniques to evaluate the porosity are relatively time consuming and somewhat expensive. In the present work, we evaluated a technique known as thermoporometry (TPM). The technique does not require complicated preparation of samples and allows the evaluation of the size and distribution of the pores by the measurement of the thermal behavior of the samples by DSC equipment. This work presents in a comparative way the evaluation of two samples of microgels, a poly(acrylic acid) microgel (pAA) and a co-polymer microgel of poly(acrylic acid-co-N-isopropylacrylamide) p(AA-co-NiPAM). The goal is to show the method sensitivity to study different samples of gels. The results showed that the porous structures of these microgels, expressed by their pore size distribution are different, which is an indicative that the method had the sensitivity to identify this difference.

Hydrogels of acrylic acid were produced through solution free radical polymerization at 70 °C. The materials obtained were put in contact with D‐fructose solution and the swelling behaviour was registered. The swollen hydrogels were immersed in distilled water and the D‐fructose released was quantified in real time by a low‐cost polarized light optoelectronic detection system. A simplified mathematical model was developed in order to represent the system under study. This model was tested against experimental data, showing good agreement. Additionally, the effect of the model parameters on the prediction profiles was evaluated.

RESUMO -O presente trabalho teve como objetivo obter e caracterizar lipases deAspergillus niger C e 11T53A14 imobilizadas por gelificação iônica. Utilizando pnitrofenil octanoato como substrato, foram avaliados o pH ótimo de reação, especificidade frente a p-nitrofenil esteres e estabilidade operacional. A lipase de A. niger C imobilizada só apresentou atividade para pH 7 e 6, teve maior afinidade para C4 e perdeu 60% da atividade inicial após o 1° ciclo e posteriormente manteve constante. Quanto a lipase de A. niger 11T53A14 imobilizada esta apresentou atividade para pH 7 e 6, teve maior afinidade para C4 e C18 e perdeu cerca de 95% da atividade inicial após o 5° ciclo.

Trata-se de um estudo qualitativo e descritivo, cujo o objetivo foi verificar a percepção de cuidadores acerca de pacientes com transtornos mentais atendidos na rede pública de saúde na cidade de Montes Claros-MG. O trabalho foi desenvolvido no centro de atenção psicossocial (CAPS). Os dados foram obtidos através da realização de um grupo focal e analisados através da técnica de análise do discurso. Após a coleta de dados surgiram categorias relacionadas as dificuldades e desafios encontrados pelos cuidadores, comportamento do paciente e sobrecarga dos cuidadores. Concluiu-se que o familiar cuidador do portador de transtorno mental apresenta sofrimento e carência de informação. Isso demonstra a necessidade da aproximar a equipe de saúde ao cuidador, pois essa interação poderá contribuir no processo de amenização da responsabilidade do ato de cuidar

In this work, silver nanoparticles (AgNPs) were obtained by a chemical reduction method using different chitosan salts as stabilizing agents, able to protect and prevent against the aggregation of the nanoparticles. Various chitosan salts with different organic acids, which included: acetic, succinic, formic, propionic, malic, glycolic and lactic acid were used to form the chitosan salts. The use of these organic acids represents a viable, sustainable, environmentally friendly and economical way to synthesized AgNPs. The AgNPs‐chitosan salts samples were analyzed by UV‐VIS, ATR‐FTIR spectroscopy, DLS, and TEM. Most of the organic acids led to nanoparticles with small dimensions (30–52 nm) and positive zeta‐potential. However, those AgNPs‐chitosan that were stabilized by the salts of α‐hydroxyacids and diacids, like glycolate and succinate, led to larger particles. The stability study under different storage conditions and time showed that the silver nanoparticles are more stable when storage at cold temperatures.