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Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-05T19:05:37Z No. of bitstreams: 1 IMARALLY VITOR DE SOUZA RIBEIRO NASCIMENTO - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2760797 bytes, checksum: 7ecba4dc55afbb264d93e04510c69d66 (MD5) / Made available in DSpace on 2018-04-05T19:05:37Z (GMT). No. of bitstreams: 1 IMARALLY VITOR DE SOUZA RIBEIRO NASCIMENTO - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2760797 bytes, checksum: 7ecba4dc55afbb264d93e04510c69d66 (MD5) Previous issue date: 2014-08-29 / Capes / Os sistemas de liberação controlada de fármacos oferecem inúmeras vantagens quando comparados a outros de dosagem convencional tendo os polissacarídeos biodegradáveis ganhando bastante aceitação no desenvolvimento desses sistemas. A quitosana é um exemplo de polissacarídeo biodegradáveis, cuja taxa de liberação pode ser modulada a partir da reticulação iônica com o Tripolifosfato de sódio (TPP). A piperina é um dos principais constituintes da pimenta negra, possuindo diversas ações farmacológicas que podem causar a morte de células cancerígenas e quando conjugada com a quitosana apresenta melhor biodisponibilidade e ação mais rápida. Sendo assim, esse trabalho objetivou desenvolver e avaliar comparativamente membranas poliméricas de quitosana e quitosana reticulada pelo TPP para uso em sistema de liberação controlada de piperina, com a finalidade de obter uma via alternativa para a administração desse fármaco. A piperina foi adicionada sob agitação constante à solução de quitosana e as membranas foram obtidas pelo método de evaporação do solvente. As membranas desenvolvidas foram caracterizadas pelas técnicas de Espectroscopia na Região do Infravermelho com Transformada de Fourier (FTIR), Difração de Raios X (DRX), Microscopia Ótica (MO), Microscopia Eletrônica de Varredura (MEV), Espectroscopia por Energia Dispersiva de Raios X (EDS), Análise Termogravimétrica (TG), Análise de Calorimetria Exploratória Diferencia (DSC), Eficiência de Carregamento (EC) através da Cromatografia Liquida de Ultra Eficiência (CLUE), Avaliação da Viabilidade Celular dos Macrófagos (MTT). Observou-se na análise por FTIR bandas características da quitosana, do agente reticulante e da piperina, como também bandas que caracterizam uma interação entre a quitosana e a piperina. A técnica de DRX demonstrou alteração no caráter semicristalino da quitosana com a presença da piperina e do tripolifosfato. Foi possível perceber, através das técnicas de MO e MEV, alteração na morfologia da membrana contendo piperina quando comparada a de quitosana pura, com a presença de partículas fibrilares. As análises de TG e DSC evidenciaram que quando a piperina foi adicionada à quitosana esta proporcionou uma maior estabilidade térmica ao sistema. O ensaio eficiência de carregamento evidenciou que a extração do o fármaco foi eficaz e que a reticulação influenciou na extração deste. As membranas desenvolvidas apresentaram potencial citotóxico para as células de câncer mamário humano MCF 7. Nas condições desenvolvidas nesta pesquisa o sistema indicado como referência para ensaios de liberação e novos ensaios biológicos é o sistema MQPR. Diante do exposto o sistema desenvolvido apresenta-se como promissor para a obtenção de um sistema para liberação controlada de fármacos. / Controlled drug delivery systems offer many advantages when compared to other conventional dosage methods with biodegradable polysaccharides gaining enough acceptance in the development of these systems. Chitosan is an example of a biodegradable polysaccharide, whose rate of release can be modulated from the ionic crosslinking with sodium tripolyphosphate (TPP). Piperine is one of the major constituent of black pepper, having many pharmacological actions that can cause the death of cancer cells and when combined with chitosan has better bioavailability and faster action. Therefore, this study aimed to develop and comparatively evaluate polymer membranes of chitosan and crosslinked chitosan by TPP to be used in a controlled release system of piperine, in order to obtain an alternative route for the administration of this drug system. Piperine was added under constant stirring to the solution of chitosan and membranes were obtained by the solvent evaporation method. The developed membranes were characterized by the techniques of Infrared Spectroscopy in the Region Fourier Transform (FTIR), X-ray Diffraction (XRD), Optical Microscopy (OM), scanning electron microscopy (SEM), Energy Dispersive Spectroscopy X-Ray (EDS), Thermogravimetric Analysis (TGA), Scanning Calorimetry Analysis of Difference (DSC), Efficiency Charge (EC) by liquid Chromatography Ultra Efficiency (HPLC), Assessment of Cell Viability of Macrophages (MTT). It was observed by FTIR analysis, bands characteristic of chitosan, the crosslinking agent and piperine, as well as bands characterizing an interaction between chitosan and piperine. The XRD technique showed change in semi-crystalline nature of chitosan in the presence of piperine and tripolyphosphate. It was possible to see, through the techniques of OM and SEM, changes in the morphology of the membrane containing piperine compared to pure chitosan, with the presence of fibrillar particles. TG analysis showed that, when piperine was added to the chitosan it provided a smaller weight loss of the system, showing the interaction between chitosan and piperine. DSC analysis showed that addition of piperine into chitosan provided greater stability to the system. The charging efficiency test showed that the drug can be entrapped by 57% in the uncrosslinked membranes and crosslinking influenced the extraction of drug. The developed membranes showed cytotoxic potential for human breast cancer cells MCF 7. Under the developed conditions in this research, MQPR system was shown as a reference for drug delivery testing and new biological tests. Given the above, the developed system is presented as promising for obtaining a system for controlled release of drugs.

This experimental work investigated the development and testing of a controlled release system for methionine. Methionine is one of the limiting amino acids for the milk production in dairy cows. The quantities of methionine which reach the small intestine are affected by the bacteria in the rumen which utilize methionine. A controlled release system which will offer a protective barrier for methionine may ensure that the methionine reaches the small intestine in sufficient quantities. The work involved the development of a coating around methionine crystals, which would act as a barrier, protecting it from the rumen conditions. Zein and kafirin proteins from maize and sorghum, respectively, were used as the principal coating components for the controlled release system. Two different approaches were used in the development of the controlled release system. First, the zein and kafirin proteins were tested for their ability to act as barriers for the controlled release of methionine, and second, zein and kafirin microparticles were used as the controlled release agents. Relatively successful, laboratory-scale methods were developed for coating the methionine with the proteins and the microparticles. Protein coatings were made by addition of methionine crystals to acid-dissolved proteins which led to the formation of a protein/methionine matrix. For coating the methionine with microparticles, glacial acetic acid was used to fuse microparticles around the methionine crystals. Dissolution assays were performed to test the release of methionine from the coatings under simulated rumen conditions. Both the zein and kafirin and microparticle coatings exhibited a barrier effect for methionine. The barrier effects of these coatings were influenced by several factors. Increasing the proportion of the coating agents led to improved barrier properties. However, this only occurred until a certain proportion of coating agent was present (50%), after which the barrier properties no longer increased. Heat treatment of the coatings also increased the barrier properties of the coatings. This may be due to the formation of disulphide cross-links being formed during the application of heat. When a simple extrusion method was used to form the coatings, the barrier properties also improved in comparison to those coatings which were not formed using extrusion. When producing the microparticles, it was found that only the laboratory extracted kafirin preparation with 85% (db) protein formed microparticles. It was hypothesized that microparticle formation might be related to the purity of the protein preparations. Scanning electron microscopy of the coatings after the dissolution tests and pepsin digestion revealed pores on the surface of the coating. These were probably where the methionine leached from the coating into the dissolution medium. The protein coatings did act as partial barriers, extending the release of methionine. From the release curves of methionine from the coatings, it could be seen that a sustained release of methionine occurred over a period of time, rather than a controlled release of methionine at a certain time. The aim of the application was thus only partially achieved as a complete protective barrier for methionine was not obtained from the protein coatings. No significant difference between the barrier properties of the coatings prepared from the proteins themselves and the microparticles were found. However, when based on equal protein purity the kafirin protein coatings showed the most effective barrier properties. Further research regarding kafirin coatings as a controlled release agent is recommended based on the results of the above named calculation. This research would entail investigating various coating technologies and methods. / Dissertation (MSc)--University of Pretoria, 2011. / Food Science / unrestricted

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Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-11T15:06:17Z No. of bitstreams: 1 LEONARDO FALCÃO FEITOSA - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2258061 bytes, checksum: cdc233909fd365937aacd1ef5fa7c2cd (MD5) / Made available in DSpace on 2018-04-11T15:06:17Z (GMT). No. of bitstreams: 1 LEONARDO FALCÃO FEITOSA - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2258061 bytes, checksum: cdc233909fd365937aacd1ef5fa7c2cd (MD5) Previous issue date: 2014-12-29 / Na terapia medicamentosa convencional o fármaco é administrado através de uma forma farmacêutica e produz um nível tecidual do fármaco que não se mantêm dentro da faixa terapêutica por um período prolongado de tempo. Desta forma, o êxito do tratamento vai depender de vários fatores como dosagens precisas e frequentes em horários específicos pré-determinados e adesão do paciente à terapêutica de modo que, a não obediência ao esquema terapêutico, pode resultar em utilização do fármaco em faixa não efetiva ou em níveis tóxicos Devido a grande problemática da manutenção de níveis séricos de fármacos no organismo humano, principalmente quando se tratam se fármacos relacionados ao tratamento de dores de moderadas a intensa, este trabalho propõe o desenvolvimento de membranas porosas a base de quitosana, que é um polímero natural biocompatível, capazes de promover a liberação controlada de fentanil. As matrizes obtidas foram caracterizadas por: MO, MEV, EDS, FTIR, DRX, Ensaio de Intumescimento, Ensaio de Biodegradação e Ensaio de Citotoxicidade. Por MO e MEV verificou-se uma superfície com poros aparentemente interconectados. A partir da análise por EDS pode-se verificar os elementos componentes da quitosana e do fármaco. Por FTIR e DRX notou-se a não alteração dos grupos funcionais e cristalinidade, respectivamente, do material devido a incorporação do fármaco. Baseado nos ensaios de intumescimentos e biodegradação verificou-se a capacidade de controlar as variáveis: razão de intumescimento e taxa de degradação exclusivamente pela variação da concentração de quitosana na membrana porosa. Verificou-se no ensaio de citotoxicidade que as membranas, mesmo com a incorporação do fármaco, não apresentaram citotoxicidade. Baseado nos resultados obtidos pôde-se concluir que é possível sintetizar uma matriz polimérica com promissoras propriedades para carrear fármaco e para testes in vivo. / In conventional medical therapy the drug is administered via a dosage form and produces a tissue level of the drug that is not maintained within the therapeutic range over an extended period of time. Thus, the success of the treatment will depend on several factors such as accurate and frequent dosing at predetermined specific times and patient adherence to therapy so that the non-compliance to the treatment regimen can result in use of the drug in not effective range or toxic levels Due to the great problem of maintaining serum levels of drugs in the human body, especially in the case if drugs related to the treatment of moderate to severe pain, this paper proposes the development of porous membranes chitosan base, which is a biocompatible natural polymer, capable of promoting the controlled release of fentanyl. The matrices obtained were characterized by: OM, SEM, EDS, FTIR, XRD, Swelling test, biodegradation test and Cytotoxicity Assay. For OM and SEM there was apparently a surface with interconnected pores. From the EDS analysis can verify the elements of chitosan and drug. FTIR and XRD noted not to change functional groups of crystallinity and, respectively, of the material due to the incorporation of the drug. Based on swellings and biodegradation tests verified the ability to control the following variables: swelling ratio and degradation rate solely by varying the concentration of the chitosan porous membrane. It was found that the cytotoxicity assay the membranes, even with the incorporation of the drug did not show cytotoxicity. Based on the results obtained it was concluded that it is possible to synthesize a polymer matrix with promising properties to adduce drug and in vivo tests.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-04T20:45:16Z No. of bitstreams: 1 DAYSE DE LOURDES MADRGA ESPÍNOLA GUEDES - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2225179 bytes, checksum: ad9f795a81034cb79500cb575de58f73 (MD5) / Made available in DSpace on 2018-04-04T20:45:16Z (GMT). No. of bitstreams: 1 DAYSE DE LOURDES MADRGA ESPÍNOLA GUEDES - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2225179 bytes, checksum: ad9f795a81034cb79500cb575de58f73 (MD5) Previous issue date: 2014-12-12 / A presente pesquisa tem como objetivo, caracterizar filmes de quitosana, de aplicação sublingual, para uso em sistemas de liberação controlada de fumarato de formoterol., buscando uma nova alternativa para o tratamento emergencial das crises de asma. Sabemos que a asma é uma patologia de grande incidência no Brasil e no mundo, pois existem cerca de 300 milhões de pessoas acometidas pela doença a nível mundial e 20 milhões de brasileiros .É uma doença de caráter hereditário, crônica que não tem cura e que se apresenta muitas vezes como uma emergência médica , pois nas crises da doença o socorro deve ser imediato com o intuito de evitar o óbito do paciente. Hoje utiliza-se apenas a via inalatória como preferencial para administração dos broncodilatadores, visto que essa via tem rapidez de ação. No entando, deparamo-nos com a difícil técnica de utilização dos inaladores que veiculam o medicamento o que muitas vezes impossibilita a sua utilização especialmente em crianças, idosos e pacientes muito debilidados. Vendo esta dificuldade, propusemos com o nosso trabalho buscar uma nova via de utilização dos medicamentos broncodilatadores, que tivesse a mesma eficácia da via inalatória, dispensando a difícil técnica de utilização dos fármacos .Para isso , escolhemos a via sublingual de rápida ação e facilidade de utilização, podendo ser empregada mais adequadamente em uma crise de asma . Selecionamos a quitosana, por ser um biopolímero versátil e muito utilizado em sistema de liberação controlada de fármaco para veicular o formoterol , que é um potente broncodilatador, através da produção de um filme para deposição sublingual. E os resultados obtidos através das caracterizações apresentaram membranas com variações de cristalinidade (por DRX) de acordo com o processo de reticulação, além de apresentarem uma possível relação entre reticulação e liberação. Por FTIR pode-se observar certa interação entre o fármaco e os grupos amina da quitosana, assim como possível isomerização do fármaco pela reticulação com 5% de TPP. Pelas microscopias ótica e eletrônica, pode-se observar que o acréscimo de fármaco proporcionou alguma rugosidade a membrana. Também pelas microscopias verificou-se a reticulação não homogênea da superfície da membrana. Por EDS não se verificou nenhum elemento estranho a estrutura da quitosana e do fármaco. Por medida do ângulo de molhabilidade pode-se verificar aumento do perfil hidrofílico da membrana por adição do fármaco, perfil este que não foi modificado pelo processo de reticulação. O ensaio de citotoxicidade apresentou resultados que indicam a membrana como promissora candidata a testes in vivo. / This research aims to characterize chitosan films, sublingual application, for use in controlled release of formoterol fumarate systems., Looking for a new alternative for the emergency treatment of asthma attacks. We know that asthma is a disease of high incidence in Brazil and in the world, because we have about 300milhões of people with the disease worldwide and 20 million Brazilians .It is one hereditary disease, chronic that has no cure and that often presents as a medical emergency, because the crisis of the disease the relief should be immediate in order to prevent the death of the patient. Today only is used inhalation as preferred for administration of bronchodilators, since this route has faster action .In entando, we are faced with the difficult technique for using inhalers that deliver the medicine which often makes it impossible to use especially in children, the elderly and very debilidados patients. Buy this difficulty, we proposed in our work to seek a new route for the use of bronchodilators, which had the same effectiveness of inhaled, eliminating the difficult technique of using drugs .For this, choose the sublingual route of fast action and ease of use and can be used more appropriately in an asthma attack. Chitosan selected because it is a versatile and widely used biopolymer for controlled drug delivery system for conveying formoterol, which is a potent bronchodilator, by producing a film for sublingual deposition. And the results obtained from the characterization showed membranes crystallinity variations (XRD) according to the crosslinking process, besides presenting a possible relationship between cross-linking and release. By FTIR one can observe some interaction between the drug and amino groups of chitosan, and can isomerization of drug by crosslinking with 5% TPP. Through optical and electronic microscopy, it can be seen that addition of drug has provided some roughness to the membrane. Also by microscopy verified the inhomogeneous crosslinking of the membrane surface. EDS there was no foreign object the structure of chitosan and the drug. By measuring the wetting angle can be checked increase the hydrophilic profile of the membrane by addition of the drug, this profile has not been modified by crosslinking process. The cytotoxicity assay results presented indicate that the membrane as a promising candidate for in vivo testing.