Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-11-27T15:27:51Z No. of bitstreams: 1 BentoPereiraDaCostaNeto_TESE.pdf: 3073031 bytes, checksum: 4f719387480280ad7c6a1e4378580451 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2015-11-30T23:35:19Z (GMT) No. of bitstreams: 1 BentoPereiraDaCostaNeto_TESE.pdf: 3073031 bytes, checksum: 4f719387480280ad7c6a1e4378580451 (MD5) / Made available in DSpace on 2015-11-30T23:35:19Z (GMT). No. of bitstreams: 1 BentoPereiraDaCostaNeto_TESE.pdf: 3073031 bytes, checksum: 4f719387480280ad7c6a1e4378580451 (MD5) Previous issue date: 2014-05-05 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Micropart?culas biodegrad?veis s?o utilizadas como sistemas de libera??o controlada de f?rmacos e est?o em constante desenvolvimento e aperfei?oamento (novos materiais, novos processos, entre outros). Quitosana representa uma alternativa interessante de biomaterial devido ?s suas caracter?sticas f?sico-qu?micas e biol?gicas. Micropart?culas de quitosana apresentam-se como sistemas promissores para carreamento e libera??o controlada de f?rmacos e vacinas principalmente por vias n?o invasivas de administra??o como as vias de mucosa. O controle da velocidade e da capacidade de intumescimento destes sistemas em meio ?cido s?o os principais fatores limitantes que precisam ser superados para que micropart?culas de quitosana possam ter todo o seu potencial de aplica??o explorado no campo farmac?utico. Existem muitos estudos referentes a modifica??es da estrutura de micropart?culas de quitosana atrav?s de t?cnicas diversas (reticula??o qu?mica, blendas com outros pol?meros, s?ntese de novos materiais h?bridos org?nico-inorg?nico com a finalidade de modificar estas propriedades que comprometem o uso da quitosana no desenvolvimento de sistemas de libera??o controlada. A proposta deste trabalho foi de conceber e desenvolver um novo tipo de ve?culo para libera??o controlada ? base de quitosana. Nanopart?culas de s?lica (Aerosil? foram incorporadas ? uma solu??o de quitosana para gerar micropart?culas de quitosana nanoestruturadas com s?lica ? partir da evapora??o do solvente (?gua) atrav?s de um processo de secagem por spray drying. As micropart?culas obtidas foram caracterizadas atrav?s de diferentes t?cnicas (espetroscopia infravermelho, difra??o de raios X, calorimetria diferencial de varredura, an?lise termogravim?trica, microscopia eletr?nica de varredura e microscopia eletr?nica de transmiss?o foram utilizadas para caracterizar as micropart?culas, tamb?m foram feitas estabilidade ?cida, capacidade de sor??o de umidade, propriedades de libera??o e ensaios biol?gicos. As micropart?culas nanoestruturadas com s?lica hidrof?bica (Aerosil? R972) apresentaram maior degrada??o t?rmica, a afinidade de ?gua mais baixo, melhor estabilidade ?cida e capacidade de retardar a rifampicina e cloridrato de propranolol (modelos de drogas) a libera??o em condi??es fisiol?gicas simuladas. Estudos de biocompatibilidade in vitro indicaram baixa citotoxicidade e baixa capacidade de ativar a produ??o de ?xido n?trico das c?lulas, sendo compat?vel com uma baixa a??o pr?-inflamat?ria, encorajando mais estudos sobre a utiliza??o das micropart?culas de quitosana nanoestruturadas com Aerosil? como os sistemas carreadores de f?rmacos por via oral ou nasal. / Biodegradable microspheres used as controlled release systems are important in pharmaceutics. Chitosan biopolymer represents an attractive biomaterial alternative because of its physicochemical and biological characteristics. Chitosan microspheres are expected to become promising carrier systems for drug and vaccine delivery, especially for non-invasive ways oral, mucosal and transdermal routes. Controlling the swelling rate and swelling capacity of the hydrogel and improving the fragile nature of microspheres under acidic conditions are the key challenges that need to be overcomed in order to enable the exploration of the full pharmaceutical potential use of these microparticles. Many studies have focused on the modification of chitosan microsphere structures with cross-linkers, various polymers blends and new organic-inorganic hybrid systems in order to obtain improved properties. In this work, microspheres made of chitosan and nanosized hydrophobic silica (Aerosil R972) were produced by a method consisting of two steps. First, a preparation of a macroscopically homogeneous chitosan-hydrophobic silica dispersion was prepared followed by spray drying. FTIR spectroscopy, X-ray powder diffraction, differential scanning calorimetry, thermal gravimetric analysis, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (TEM) were used to characterize the microspheres. Also, the were conducted acid stability, moisture sorption capacity, release properties and biological assays. The chitosan-hydrophobic silica composite microspheres showed improved thermal degradation, lower water affinity, better acid stability and ability to retard rifampicin and propranolol hydrochloride (drug models) release under simulated physiological conditions. In vitro biocompatibility studies indicated low cytotoxicity and low capacity to activate cell production of the pro-inflammatory mediator nitric oxide. The results show here encourage further studies on the use of the new chitosan-hydrophobic silica composite microspheres as drug carrier systems via oral or nasal routes.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-09T23:24:53Z No. of bitstreams: 1 ChristianeSiqueiraDeAzevedoSa_DISSERT.pdf: 2601824 bytes, checksum: 192560f3b8d14a03aa0da8a4f6dc9924 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-11T22:01:19Z (GMT) No. of bitstreams: 1 ChristianeSiqueiraDeAzevedoSa_DISSERT.pdf: 2601824 bytes, checksum: 192560f3b8d14a03aa0da8a4f6dc9924 (MD5) / Made available in DSpace on 2016-03-11T22:01:19Z (GMT). No. of bitstreams: 1 ChristianeSiqueiraDeAzevedoSa_DISSERT.pdf: 2601824 bytes, checksum: 192560f3b8d14a03aa0da8a4f6dc9924 (MD5) Previous issue date: 2015-02-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Os materiais t?xteis inteligentes e funcionais t?m sido amplamente desenvolvidos e pesquisados com a finalidade de serem utilizados em v?rias ?reas da ci?ncia e tecnologia. Esses materiais fibrosos necessitam de diferentes propriedades qu?micas e f?sicas para se tornarem materiais multifuncionais. Com o advento da nanotecnologia, as t?cnicas desenvolvidas t?m sido ferramentas essenciais para caracterizar qualitativamente esses novos materiais. Ultimamente a aplica??o de micro e nanomateriais em substratos t?xteis tem sido objeto de muitas pesquisas. Muitos desses nanomateriais n?o tem sido otimizado, e os custos para sua aplica??o e a polui??o ao meio ambiente vem aumentando, pois ainda n?o existe tratamento de efluentes contento esses nanomateriais. As fibras de soja t?m baixa adsor??o de micro e nanoc?psulas termosenss?veis devido a sua incompatibilidade de suas cargas superficiais. No presente trabalho utilizou-se a s?ntese da quitosana para previamente funcionalizar as fibras de soja. A quitosana ? um polieletr?lito natural apresentando alta densidade de cargas positivas, as fibras de soja apresentam cargas negativas bem como, as micro/nanoc?psulas, com isso a quitosana atua como agente cationizador da fibra. Neste caso a quitosana atua como agente auxiliar cationizador para fixar as microc?psulas termosenss?veis no substrato t?xtil. Para a caracteriza??o do polieletr?lito foram feitas as an?lises do tamanho das part?culas, potencial zeta, bem como as an?lises morfol?gicas (MEV e DRX), an?lises das propriedades t?rmicas (TG), an?lise da Calorimetria Explorat?ria Diferencial (DSC), an?lise por Espectroscopia na Regi?o do Infravermelho com Transformada de Fourier (FTIR), colorimetria via espectro de UV-VIS foram simultaneamente realizadas no substrato utilizado. No potencial zeta e na determina??o do tamanho das part?culas foi observada a estabilidade eletrost?tica da quitosana em torno de 31.55mV e 291,0 nm respectivamente. O resultado obtido com (GD) para o material extra?do de camar?o foi de 70%, que de acordo com a literatura pode ser considerada como quitosana. Para otimiza??o do processo de tingimento foi usado um software estat?stico, o Design expert. A funcionaliza??o do substrato t?xtil com 2% de quitosana apresentou o melhor resultado de K/S, sendo o par?metro utilizado para o planejamento experimental juntamente com as vari?veis, tendo demonstrado a melhor resposta de tingimento na faixa de 2,624 de absorb?ncia. Verificou-se tamb?m que a malha de soja tingida com as nano/microc?psulas termosenss?veis apresentou excelente propriedade de solidez a lavagem, que foi observada ap?s 25 lavagens caseiras e valores significativos de K/S. / Intelligent and functional Textile Materials have been widely developed and researched with the purpose of being used in several areas of science and technology. These fibrous materials require different chemical and physical properties to obtain a multifunctional material. With the advent of nanotechnology, the techniques developed, being used as essential tools to characterize these new materials qualitatively. Lately the application of micro and nanomaterials in textile substrates has been the objective of many studies, but many of these nanomaterials have not been optimized for their application, which has resulted in increased costs and environmental pollution, because there is still no satisfactory effluent treatment available for these nanomaterials. Soybean fiber has low adsorption for thermosensitive micro and nanocapsules due to their incompatibility of their surface charges. For this reason, in this work initially chitosan was synthesized to functionalise soybean fibres. Chitosan is a natural polyelectrolyte with a high density of positive charges, these fibres have negative charges as well as the micro/nanoc?psules, for this reason the chitosan acts as auxiliary agent to cationize in order to fix the thermosensitive microcapsules in the textile substrate. Polyelectrolyte was characterized using particle size analyses and the measurement of zeta potential. For the morphological analysis scanning Electron Microscopy (SEM) and x-Ray Diffraction (XRD) and to study the thermal properties, thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Near Infrared Spectroscopy analysis in the Region of the Fourier Transform Infrared (FTIR), colourimetry using UV-VIS spectrum were simultaneously performed on the substrate. From the measurement of zeta potential and in the determination of the particle size, stability of electrostatic chitosan was observed around 31.55mV and 291.0 nm respectively. The result obtained with (GD) for chitosan extracted from shrimp was 70 %, which according to the literature survey can be considered as chitosan. To optimize the dyeing process a statistical software, Design expert was used. The surface functionalisation of textile substrate with 2% chitosan showed the best result of K/S, being the parameter used for the experimental design, in which this showed the best response of dyeing absorbance in the range of 2.624. It was noted that soy knitting dyed with the thermosensitive micro andnanocapsules property showed excellent washing solidity, which was observed after 25 home washes, and significant K/S values.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-30T22:35:16Z No. of bitstreams: 1 AnnePriscilaOliveiraDaSilva_TESE.pdf: 3069321 bytes, checksum: 2f4ab5c7c55c4cc46520840208eb2ad3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-01T19:56:29Z (GMT) No. of bitstreams: 1 AnnePriscilaOliveiraDaSilva_TESE.pdf: 3069321 bytes, checksum: 2f4ab5c7c55c4cc46520840208eb2ad3 (MD5) / Made available in DSpace on 2016-06-01T19:56:29Z (GMT). No. of bitstreams: 1 AnnePriscilaOliveiraDaSilva_TESE.pdf: 3069321 bytes, checksum: 2f4ab5c7c55c4cc46520840208eb2ad3 (MD5) Previous issue date: 2015-07-10 / Nos ?ltimos anos, v?m sendo desenvolvidas pesquisas para obten??o de novos materiais e metodologias que visam minimizar problemas ambientais decorrente do descarte de efluentes industriais contaminados com metais pesados e ?leo. A adsor??o vem sendo utilizada como uma tecnologia alternativa eficaz, economicamente vi?vel e potencialmente importante para a redu??o destes contaminantes, principalmente quando se utiliza adsorventes naturais como alguns tipos de argilas. Os argilominerais vermiculita e a bentonita como tamb?m o biopol?mero quitosana v?m sendo utilizados como materiais adsorventes de baixo custo. O presente trabalho teve como objetivo avaliar a funcionalidade dos materiais h?bridos obtidos atrav?s da utiliza??o dos argilominerais, vermiculita expandida e bentonita, com a quitosana com o intuito da redu??o do teor de ?leo e dos ?ons met?licos para aplica??o em ?guas de produ??o gerada pela ind?stria de petr?leo. Os materiais obtidos foram caracterizados por difra??o de raios-X (DRX), espectroscopia na regi?o do infravermelho (IV), an?lises termogravim?tricas (TG/DTG), microscopia de varredura eletr?nica (MEV) e ?rea espec?fica (BET). Os resultados de DRX e MEV n?o demonstraram uma mudan?a significativa na estrutura nos argilominerais revestidos com quitosana em compara??o a sua forma natural. Nos resultados de IV observou-se a presen?a da quitosana na superf?cie dos argilominerais, devido ao aumento da intensidade das bandas de absor??o caracter?sticas do material org?nico. Os ensaios de adsor??o realizados inicialmente atrav?s de um planejamento 22 demonstraram que a quitosana tem maior capacidade adsortiva do que a vermiculita natural, com um m?ximo de 89,22 % em m?dia para concentra??es de 1000 mg/L. Os resultados mostram que a capacidade de remo??o dos ?ons atrav?s da quitosana foi, em m?dia, de 92,84 % para cobre em concentra??es na faixa de 100 mg/L e de 41,87 % para concentra??es em torno de 750 mg /L ap?s 24 horas de contato. Atrav?s dos resultados, pode-se concluir que a incorpora??o do pol?mero propicia um melhoramento na capacidade adsortiva dos argilominerais estudados, uma alternativa para utiliza??o de materiais de baixo custo para redu??o de contaminantes oriundos da ?gua de produ??o. / In recent years, researches have been developed to obtain new materials and methodologies aimed at minimizing environmental problems resulting from discharges of industrial effluents contaminated with heavy metals and oil. The adsorption has been used as an alternative technology effectively, economically viable and potentially important for the reduction of these contaminants, particularly when using natural adsorbents such as some types of clays. The vermiculite and bentonite clay as well as the biopolymer chitosan materials have been used as low-cost adsorbents. This study aimed to evaluate the potentiality of the hybrid materials obtained through the use of clay (expanded vermiculite and bentonite), with the chitosan with the aim of reducing the oil content and the metal ions for use in production waters generated by petroleum industry. The materials were characterized by diffraction of X-ray (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG / DTG), scanning electron microscopy (SEM) and gas adsorption measurements to textural analyzes. The XRD and SEM data, showed no significant change in the structures of clay mineral coated with chitosan in comparison to its shape natural. The results of FTIR observed that the presence of chitosan on the surface of clay minerals, due to the increased intensity of the characteristic absorption bands of the organic material. The adsorption tests conducted initially through a 22 planning showed that chitosan has a higher adsorption capacity than the natural vermiculite with a maximum of 89.22% on average for concentrations of 1000 mg/L. The results show that the capacity of removing ions by chitosan was, on average, 92.84% for copper concentrations in the range of 100 mg/L and 41.87 % at concentrations around 750 mg/L after 24 hours of contact. From the results it can be concluded that the incorporation of the polymer provides an improvement in adsorptive capacity of clay minerals studied an alternative to using low cost materials to reduce contaminants originating from the production water.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-09T22:44:46Z No. of bitstreams: 1 JessicaSouzaMarques_TESE.pdf: 2267676 bytes, checksum: f71e2156c17464c73f99c0aec00ef206 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-10T22:44:23Z (GMT) No. of bitstreams: 1 JessicaSouzaMarques_TESE.pdf: 2267676 bytes, checksum: f71e2156c17464c73f99c0aec00ef206 (MD5) / Made available in DSpace on 2016-08-10T22:44:23Z (GMT). No. of bitstreams: 1 JessicaSouzaMarques_TESE.pdf: 2267676 bytes, checksum: f71e2156c17464c73f99c0aec00ef206 (MD5) Previous issue date: 2015-12-14 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho foram produzidas membranas de quitosana reticuladas ionicamente, utilizando o ?cido sulf?rico como agente de reticula??o para serem aplicadas no tratamento de ?guas residuais da ind?stria do petr?leo. Duas metodologias de reticula??o das membranas foram desenvolvidas: homog?nea e heterog?nea. No processo homog?neo a vari?vel analisada foi a raz?o molar de SO42-/ NH3+ (1:6 e 1:4), enquanto, no processo heterog?neo o tempo de imers?o das membranas em ?cido sulf?rico foi a vari?vel em estudo, sendo utilizado tempos de 5 e 30 minutos. Os resultados de FTIR-ATR evidenciaram a forma??o de liga??es i?nicas entre os grupos NH3+protonados da quitosana e os ?ons sulfato do agente reticulante. Apenasnas membranas heterog?neas indicando um grau de reticula??o bastante pequeno para as homog?neas.As an?lises de TG/DTG e DRX confirmaram a forma??o dessas intera??es, como tamb?m demonstraram que houve a forma??o de uma nova estrutura na regi?o superficial das membranas CS5 e CS30 em rela??o ?s membranas de CS, CS16 e CS14. Os ensaios de intumescimento em meio aquoso evidenciaram que os processos de reticula??o reduziram a capacidade de sor??o das membranas. Enquanto que em meio ?cido as membranas de CS16 e CS14 aumentaram a capacidade de sor??o at? um percentual m?ximo de aproximadamente 140%, e as de CS5 e CS30 atingiram um m?ximo de 60%. As propriedades mec?nicas indicaram o comportamento r?gido e d?ctil das membranas reticuladas. Atrav?s dos experimentos de sor??o de solu??o de CuCl2, foi determinado que o m?ximo de efici?ncia foi obtido para as membranas CS16 com 73% de remo??o de cobre em pH 5,0 e 87% em pH 4,0. Os experimentos realizados com CuSO4 tamb?m resultaram em 80% de remo??o de ?ons de Cu2+ para as membranas de CS16. Tamb?m foi verificado que o aumento da concentra??o e da temperatura refletiram na diminui??o da capacidade de adsor??o para todas as membranas. Os resultados de cin?tica evidenciaram que as membranas foram melhor caracterizadas pela equa??o de pseudo-segunda-ordem. E, osEstudos de equil?brio demonstraram que as membranas de CS, CS16 e CS14 seguem o modelo de Langmuir, enquanto que as membranas de CS5 e CS30 seguem o modelo de Freundlich. Os experimentos de filtra??o resultaram em m?ximo de reten??o de ?ons de Cu2+ para as membranas de CS16 e CS5, atingindo 92 e 98% respectivamente. / In this work a chitosan (CS) ionically crosslinked were manufactured by treatment with sulfuric acid solution for application in the treatment of wastewater from oil industry. Two crosslinking process were developed: homogeneous and heterogeneous. In the homogeneous process the ratio molar of SO42-/ NH3+ (1:6 and 1:4) were the variable analyzed, denominated CS16 and CS14 respectively. In the heterogeneous process the soaking time of the membranes in sulfuric acid solution were the variable studied, being used times of 5 (CS5) and 30 (CS30) minutes. FTIR-ATR results indicated no changes in the characteristics of chitosan after homogeneous crosslinking process, while heterogeneous crosslinking showed formation of ionic bonds between protonated groups from chitosan and the crosslinking agent sulfate ions. TG/DTG and XRD analysis confirmed the formation of these interactions, as also shown the new structure on the surface region of CS5 and CS30 membranes compared to CS, CS16 e CS14. Swelling test in aqueous medium have shown that crosslinking process reduced the membrane sorption capacity. Swelling test in acid medium demonstrated that CS16 and CS14 membranes increasing the adsorption capacity up to a maximum percentage of 140% approximately, whereas the CS5 e CS30 reached a maximum of 60%. The mechanical properties indicated the stiff and ductile behavior of crosslinked membrane. Adsorption experiments of CuCl2 results that CS16 membranes reached the efficiency maximum with 73% of copper removal at pH 5.0 and 87% at pH 4.0. The experiments with CuSO4 also obtained efficiency maximum to the CS16 membrane and 80% to the removal of Cu2+ ions. Also was verified that the increase of concentration and temperature cause a decrease in the adsorption capacity for all membranes. Kinetics study indicated that pseudo-second-order obtained characterized better the membranes. Equilibrium studies demonstrated that the CS, CS16 and CS14 follow the Langmuir model, whereas CS5 and CS30 follows Freundlich model. Filtration experiments results with rejection maximum to the CS16 and CS5 membranes, reaching 92 and 98% respectively.

Made available in DSpace on 2014-12-17T14:57:53Z (GMT). No. of bitstreams: 1 SaniaMBA_TESE.pdf: 2511848 bytes, checksum: 97413b8278096d3ff64cc7f5138841e7 (MD5) Previous issue date: 2012-04-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Chitin and chitosan are nontoxic, biodegradable and biocompatible polymers produced by renewable natural sources with applications in diverse areas such as: agriculture, textile, pharmaceutical, cosmetics and biomaterials, such as gels, films and other polymeric membranes. Both have attracted greater interest of scientists and researchers as functional polymeric materials. In this context, the objective of this study was to take advantage of the waste of shrimp (Litopenaeus vannamei and Aristeus antennatus) and crabs (Ucides cordatus) from fairs, beach huts and restaurant in Natal/RN for the extraction of chitin and chitosan for the production of membranes by electrospinning process. The extraction was made through demineralization, deproteinization, deodorization and deacetylation. Morphological analyzes (SEM and XRD), Thermal analysis (TG and DTG), Spectroscopy in the Region of the Infrared with Transformed of Fourier (FTIR) analysis Calorimetry Differential Scanning (DSC) and mechanical tests for traction were performed. In (XRD) the semicrystalline structure of chitosan can be verified while the chitin had higher crystallinity. In the thermal analysis showed a dehydration process followed by decomposition, with similar behavior of carbonized material. Chitosan showed temperature of maximum degradation lower than chitin. In the analysis by Differential Scanning Calorimetry (DSC) the curves were coherent to the thermal events of the chitosan membranes. The results obtained with (DD) for chitosan extracted from Litopenaeus vannamei and Aristeus antennatus shrimp were (80.36 and 71.00%) and Ucides cordatus crabs was 74.65%. It can be observed that, with 70:30 solutions (v/v) (TFA/DCM), 60 and 90% CH3COOH, occurred better facilitate the formation of membranes, while 100:00 (v/v) (TFA/DCM) had formation of agglomerates. In relation to the monofilaments diameters of the chitosan membranes, it was noted that the capillary-collector distance of 10 cm and tensions of 25 and 30 kV contributed to the reduction of the diameters of membranes. It was found that the Young s modulus decreases with increasing concentration of chitosan in the membranes. 90% CH3COOH contributed to the increase in the deformation resulting in more flexible material. The membranes with 5% chitosan 70:30 (v/v) (TFA/DCM) had higher tensile strength / Quitina e quitosana s?o pol?meros at?xicos, biodegrad?veis e biocompat?veis produzidos por fontes naturais renov?veis com aplica??es em diversas ?reas como: agricultura, t?xtil, farmac?utica, cosm?ticos e biomateriais, tais como g?is, filmes, membranas polim?ricas entre outros. Ambas t?m despertando grande interesse de cientistas e pesquisadores como materiais polim?ricos funcionais. Nesse contexto, o objetivo do presente trabalho foi aproveitar os res?duos de camar?es (Litopenaeus vannamei e Aristeus antennatus) e de caranguejos (Ucides cordatus) proveniente de feiras, barracas de praia e restaurantes em Natal/RN para extra??o de quitina, quitosana e produ??o de membranas pelo processo de eletrofia??o. A extra??o foi realizada a partir das etapas de desmineraliza??o, desproteiniza??o, desodoriza??o e desacetila??o. An?lises morfol?gicas (MEV e DRX), an?lises das propriedades t?rmicas (TG e DTG), an?lise por Espectroscopia na Regi?o do Infravermelho com Transformada de Fourier (FTIR), an?lise de Calorimetria Explorat?ria Diferencial (DSC) e ensaios mec?nicos por tra??o foram realizados. Na an?lise de DRX pode-se verificar a estrutura semicristalina da quitosana enquanto a quitina teve alta cristalinidade. As an?lises t?rmicas demonstraram um processo de desidrata??o seguido da decomposi??o com comportamento similar de material carbonizado. A quitosana apresentou temperaturas de m?xima degrada??o mais baixas do que a quitina. Na an?lise por Calorimetria Explorat?ria Diferencial (DSC) as curvas foram coerentes aos eventos t?rmicos das membranas de quitosana. Os resultados obtidos com (GD) para quitosana extra?da de camar?es Litopenaeus vannamei e Aristeus antennatus foram (80,36 e 71,00%) e caranguejos Ucides cordatus foi 74,65%. Pode-se perceber que, com solu??es 70:30 (v/v) (TFA/DCM), 60 e 90% CH3COOH, ocorreu melhor facilita??o na forma??o das membranas, enquanto em 100:00 (v/v) (TFA/DCM) houve forma??o de aglomerados. Em rela??o aos di?metros dos nanofilamentos das membranas de quitosana, percebeu-se que a dist?ncia capilar-coletor de 10 cm e tens?es de 25 e 30 kV contribu?ram para a redu??o dos di?metros das membranas. Quanto ao m?dulo de Young diminui com o aumento da concentra??o da quitosana nas membranas. 90% CH3COOH contribuiu para o aumento da deforma??o, sendo um material mais flex?vel. As membranas com 5% quitosana 70:30 (v/v) (TFA/DCM) apresentaram maior valor de resist?ncia ? tra??o

Made available in DSpace on 2014-12-17T15:01:23Z (GMT). No. of bitstreams: 1 AnnePOS_DISSERT.pdf: 3590017 bytes, checksum: be0135adc8f7169d0bb58adbac9fec95 (MD5) Previous issue date: 2010-12-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Actually, surveys have been developed for obtaining new materials and methodologies that aim to minimize environmental problems due to discharges of industrial effluents contaminated with heavy metals. The adsorption has been used as an alternative technology effectively, economically viable and potentially important for the reduction of metals, especially when using natural adsorbents such as certain types of clay. Chitosan, a polymer of natural origin, present in the shells of crustaceans and insects, has also been used for this purpose. Among the clays, vermiculite is distinguished by its good ion exchange capacity and in its expanded form enhances its properties by greatly increasing its specific surface. This study aimed to evaluate the functionality of the hybrid material obtained through the modification of expanded vermiculite with chitosan in the removal of lead ions (II) in aqueous solution. The material was characterized by infrared spectroscopy (IR) in order to evaluate the efficiency of modification of matrix, the vermiculite, the organic material, chitosan. The thermal stability of the material and the ratio clay / polymer was evaluated by thermogravimetry. To evaluate the surface of the material was used in scanning electron microscopy (SEM) and (BET). The BET analysis revealed a significant increase in surface area of vermiculite that after interaction with chitosan, was obtained a value of 21, 6156 m2 / g. Adsorption tests were performed according to the particle size, concentration and time. The results show that the capacity of removal of ions through the vermiculite was on average 88.4% for lead in concentrations ranging from 20-200 mg / L and 64.2% in the concentration range of 1000 mg / L. Regarding the particle size, there was an increase in adsorption with decreasing particle size. In fuction to the time of contact, was observed adsorption equilibrium in 60 minutes with adsorption capacity. The data of the isotherms were fitted to equation Freundlich. The kinetic study of adsorption showed that the pseudo second- order model best describes the adsorption adsorption, having been found following values K2=0,024 g. mg-1 min-1and Qmax=25,75 mg/g, value very close to the calculated Qe = 26.31 mg / g. From the results we can conclude that the material can be used in wastewater treatment systems as a source of metal ions adsorbent due to its high adsorption capacity / Nos ?ltimos anos, v?m sendo desenvolvidas pesquisas para obten??o de novos materiais e metodologias que visam minimizar problemas ambientais decorrente do descartes de efluentes industriais contaminados com metais pesados. A adsor??o vem sendo utilizada como uma tecnologia alternativa eficaz, economicamente vi?vel e potencialmente importante para a redu??o dos metais, principalmente quando se utiliza adsorventes naturais como alguns tipos de argilas. A quitosana, pol?mero de origem natural, presente na carapa?a de crust?ceos e insetos, tamb?m tem sido usada para esse fim. Dentre as argilas, a vermiculita se destaca pela sua boa capacidade de troca i?nica e na sua forma expandida potencializa suas propriedades por aumentar bastante sua superficial espec?fica. O presente trabalho teve como objetivo avaliar a funcionalidade do material h?brido obtido atrav?s da modifica??o da vermiculita expandida com quitosana na remo??o de ?ons de chumbo (II) em efluentes aquosos. O material obtido foi caracterizado por espectroscopia do infravermelho (IV) com o intuito de se avaliar a efici?ncia da modifica??o da matriz inorg?nica, a vermiculita, pelo material org?nico, a quitosana. A estabilidade t?rmica do material e a rela??o argila /pol?mero foram avaliadas atrav?s da termogravimetria. Para a avalia??o da superf?cie do material foi usada a microscopia de varredura eletr?nica (MEV) e (BET). A an?lise de BET revelou um aumento significativo da ?rea superficial da vermiculita que, ap?s intera??o com a quitosana, foi obtido um valor de 21, 6156 m2/g. Foram realizados ensaios de adsor??o em fun??o do tamanho de part?cula, concentra??o e tempo. Os resultados mostram que a capacidade de remo??o dos ?ons atrav?s da vermiculita foi, em m?dia, de 88,4% para chumbo em concentra??es na faixa de 20-200 mg/L e de 64,2 % na faixa de concentra??o de 1000 mg /L. Em rela??o ao tamanho de part?cula, observou-se um aumento da adsor??o com a diminui??o da granulometria. Em fun??o do tempo de contato, foi observado um equil?brio de adsor??o em 60 minutos com capacidade de adsor??o. Os dados das isotermas foram ajustados a equa??o de Freundlich. O estudo cin?tico de adsor??o mostrou que o modelo de pseudo segunda ordem descreve melhor o processo de adsor??o, sendo encontrado os seguintes valores: K2 = 0,024 g. mg-1. min-1, Qm?x= 25,75 mg/g valor bastante pr?ximo do Qe calculado = 26,31 mg/g . A partir dos resultados obtidos pode-se concluir que o material utilizado pode ser utilizado em sistemas de tratamento de efluentes como fonte adsorvente de ?ons met?licos devido a sua alta capacidade de adsor??o

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-12T13:28:17Z No. of bitstreams: 1 AlessandraLuzireneCostaTeofilo_DISSERT.pdf: 3632851 bytes, checksum: 9d450be349181a503633ee784e996b36 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-14T15:32:18Z (GMT) No. of bitstreams: 1 AlessandraLuzireneCostaTeofilo_DISSERT.pdf: 3632851 bytes, checksum: 9d450be349181a503633ee784e996b36 (MD5) / Made available in DSpace on 2018-03-14T15:32:18Z (GMT). No. of bitstreams: 1 AlessandraLuzireneCostaTeofilo_DISSERT.pdf: 3632851 bytes, checksum: 9d450be349181a503633ee784e996b36 (MD5) Previous issue date: 2017-07-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Com a descoberta dos nanotubos de carbono de parede simples (NTCPS) por Sumio Iijima, em 1991, os pesquisadores interessaram-se em sintetizar NTC em larga escala, com qualidade e baixo custo. Este trabalho prop?e uma nova metodologia e ecologicamente correta para a s?ntese de NTC por pir?lise da lignina extra?da do mesocarpo do dend? (Elaeis guineensis). Para a obten??o da amostra, a lignina foi pirolisada em um forno tubular a 1.000?C com uma determinada taxa de aquecimento 10?C/min e os experimentos foram realizados em diferentes intervalos de temperatura e sob fluxo de g?s arg?nio. Ap?s o processo de s?ntese, foi verificada a forma??o de nanomateriais de carbono. Os NTC?s foram submetidos a funcionaliza??o em solu??o (3:1) de ?cido sulf?rico (H2SO4) e ?cido n?trico (HNO3), sob agita??o, adicionado hidr?xido de am?nia (NH4OH) e lavado em seguida, neutralizado. Os nanotubos tamb?m foram funcionalizados com quitosana. O material final foi caracterizado a ?rea superficial, estrutural e propriedades f?sico-qu?micas, por meio de Difra??o de Raios X (DRX), An?lise T?rmica (TGA/DTA), Espectroscopia Raman, Microscopia Eletr?nica de Transmiss?o (MET), Espectroscopia na regi?o do Infravermelho com Transformada de Fourier com reflect?ncia difusa atenuada (FTIR/ATR) e Eletroan?lise do atrav?s de Voltametria C?clica e Imped?ncia. Os resultados demonstraram que o processo de pirolise sob fluxo de arg?nio obteve nanotubos com di?metros m?dios de 7 nm com potencial aplica??o. / With the discovery of Carbon single-wall nanotubes (SWNT?s) by Sumio Iijima in 1991, the researchers were interested in synthesizing CNT?s on a large scale, with quality and low cost. This work proposes a new methodology and ecologically correct for the synthesis of CNT?s by lignin pyrolysis extracted from the mesocarp of palm oil (Elaeis guineensis). To obtain the sample, the lignin was pyrolyzed in a tubular furnace 1.000?C with a given heating rate 10?C/min and the experiments were performed at different temperature ranges and under argon gas flow. After the synthesis process, the formation of carbon nanomaterials were verified. The CNT?s were subjected to functionalization in solution (3:1) of sulfuric acid (H2SO4) and nitric acid (HNO3) under stirring, added ammonia hydroxide (NH4OH) and washed, then neutralized. The nanotubes were also functionalized with chitosan. The final material was characterized by the surface area, structural and physical-chemical properties, using X-ray Diffraction (XRD), Thermal Analysis (TGA/DTA), Raman Spectroscopy, Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FTIR) Attenuated Total Reflection (ATR) spectroscopy and Electroanalysis through Cyclic Voltammetry and Impedance. The results showed that the pyrolysis process under argon flux obtained nanotubes with mean diameters of 7 nm with potential application. / 2018-10-10

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-10T12:12:36Z No. of bitstreams: 1 LucianaAraujoNascimento_TESE.pdf: 3313657 bytes, checksum: 8d85adb333c8ffbf5a14771e4ac06475 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-11T11:48:21Z (GMT) No. of bitstreams: 1 LucianaAraujoNascimento_TESE.pdf: 3313657 bytes, checksum: 8d85adb333c8ffbf5a14771e4ac06475 (MD5) / Made available in DSpace on 2017-01-11T11:48:21Z (GMT). No. of bitstreams: 1 LucianaAraujoNascimento_TESE.pdf: 3313657 bytes, checksum: 8d85adb333c8ffbf5a14771e4ac06475 (MD5) Previous issue date: 2016-02-24 / O objetivo do trabalho ? observar o efeito da purifica??o da quitosana (Qt) sobre a forma??o de filmes automontados utilizando complexos inorg?nicos: Na2[Fe(CN)5NO] (NPS) e cis-[Ru(bpy)2ImN(NO)](PF6)3 (RubpyNO), caracteriz?-los pelas t?cnicas de Uv-V?s, Infravermelho e voltametria c?clica. A Quitosana comercial foi purificada em tr?s diferentes formas: neutra, cloridrato e acetato. A caracteriza??o dessas apresentaram diferen?as significativas com rela??o as suas caracter?sticas como umidade, grau de desacetila??o, viscosidade e massa molar. Foi realizado o monitoramento pela t?cnica de Uv-vis do crescimento dos filmes de QtNeutra/NPS; QtAcetato/NPS; QtCloridrato/NPS; QtNeutra/ RubpyNO; QtAcetato/ RubpyNO e QtCloridrato/ RubpyNO. Dentre eles, a quitosana purificada na forma acetato mostrou melhor intera??o com os complexos, formando filmes com melhores ?ndices de correla??o R e deposi??o homog?nea dos materiais a cada bicamada formada. Essa intera??o foi confirmada pela an?lise do espectro do infravermelho dos filmes que apresentou bandas de ambos os compostos. Os estudos eletroqu?micos mostraram que os filmes formados possuem grande estabilidade, melhor resolu??o quando analisados a uma taxa de varredura de 50 mV.s-1 e que as amostras QtNeutra e QtAcetato com NPS apresentam os potenciais de pico melhores definidos sofrendo processos quase revers?veis de degrada??o. Os testes de rea??o de ?cido asc?rbico com os filmes de QtAcetato/NPS e QtAcetato/ RubpyNO mostraram que o primeiro apresentou uma melhor resposta eletroqu?mica. / Chitosan (Qt) has great technological application due to present atoxic features, biodegradable and renewable. The fact that a cationic polymer makes it capable of forming films by selfassembly technique, allowing its interaction with various compounds. In this context, this study aimed to evaluate the influence of purification of Qt in the neutral, acetate and hydrochloride forms in building self-assembled films by their interaction with nitrosyl complex (SNP and RubpyNO). Analysis of the degree of deacetylation, viscometry, infrared and thermal analysis showed that the purified Qt have different characteristics. The formation of the films was monitored by spectroscopy in the Uv-Vis region and characterized through spectroscopic techniques infrared (FTIR), thermal analysis (TG/DTG), cyclic voltammetry (CV), scanning electron microscopy (SEM) and energy dispersive X-ray (EDS). The results showed that Qt neutral and acetate forming films linear and homogeneous growth, with the interaction of both materials confirmed by FTIR technique. The results show that cyclic voltammetry of the neutral and acetate Qt films and the complex behave as semi-reversible processes, except the film QtAcetato/RubpyNO, which presents itself as an irreversible process. It was observed that chitosan affects the purification method presented in the redox process for the films due to the shape of weaker or stronger interaction of the particles according to the load presented by polycations and polyanions in solution during the formation of automounted film. The images obtained by SEM and EDS confirmed the presence of layers arranged with uniform coverage and homogeneous distribution of the elements in the film surface. The TG/DTG analysis confirmed thermal stability of the films before and after being subjected to VC. Reaction rolls of film with ascorbic acid (AA) and cysteine showed that the film QtNeutra/RubpyNO showed the best response to both substances. A straight line equation has been suggested for the determination of AA by QtNeutra/RubpyNO film and for the determination of cysteine, additional studies are required.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-10T15:32:21Z No. of bitstreams: 1 KarlaSamaraRochaSoares_TESE.pdf: 2883085 bytes, checksum: 02667bee72d9ca986a7f49f759803663 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-11T15:56:53Z (GMT) No. of bitstreams: 1 KarlaSamaraRochaSoares_TESE.pdf: 2883085 bytes, checksum: 02667bee72d9ca986a7f49f759803663 (MD5) / Made available in DSpace on 2017-01-11T15:56:53Z (GMT). No. of bitstreams: 1 KarlaSamaraRochaSoares_TESE.pdf: 2883085 bytes, checksum: 02667bee72d9ca986a7f49f759803663 (MD5) Previous issue date: 2016-05-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Acidentes com animais pe?onhentos representam um s?rio problema de sa?de p?blica em diversos pa?ses, destacando-se os acidentes of?dicos e escorpi?nicos. No Brasil, as serpentes do g?nero Bothrops e os escorpi?es pertencentes ao g?nero Tityus, s?o as de maior relev?ncia cl?nica. O tratamento para o envenenamento consiste em administra??o de soros antiof?dico e antiescorpi?nico. Vacinas que utilizam ant?genos puros e vias de administra??o alternativa requerem o uso de adjuvantes potentes e um sistema de entrega de ant?geno eficaz. Nanossistemas v?m sendo investigados como sistemas de libera??o para macromol?culas terap?uticas. A quitosana, devido as suas propriedades, tem sido extensivamente investigada na formula??o de nanocarreadores, particularmente de genes e prote?nas. Este estudo teve como objetivo a obten??o de nanopart?culas de quitosana (CNP) com base na gelifica??o i?nica para carrear prote?nas/pept?deos terap?uticos utilizados na imunoterapia e avalia??o do potencial imunoadjuvante dessas nanopart?culas na produ??o de soros antivenenos. CNP foram obtidas por gelifica??o i?nica, com tamanho m?dio de 160 nm, caracterizadas f?sico-quimicamente e o perfil de libera??o avaliado, demonstrando se tratar de um sistema de libera??o modificado. A estabilidade dos sistemas foi avaliada por 7 semanas, observando-se uma maior estabilidade dos sistemas associados aos venenos. Animais experimentais foram imunizados durante 6 semanas com 100 ?L de veneno das serpentes atrav?s inje??es subcut?neas, em diferentes concentra??es (5,0 ou 10,0%), encapsuladas em CNP ou associados ao hidr?xido de alum?nio (HA). Os resultados demonstram que os t?tulos de anticorpos obtidos para os animais vacinados com os nanossistemas foram equivalentes ou maiores aos obtidos para os animais vacinados com o HA, com a vantagem desses serem menos inflamat?rios que o HA, exigindo uma menor quantidade de ant?geno a ser administrada, por se tratar de um sistema de liberta??o modificada, revelando a obten??o de um novo sistema nanoparticulado com potencial aplica??o na soroterapia. / Accidents with venomous animals represent a serious public health problem in many countries of the world, with emphasis to snake and scorpion accidents. In Brazil, Bothrops snakes are the most clinically relevant. Regarding scorpions, the genus Tityus includes the species of higher medical importance. Treatment for envenomation consists mainly in the administration of antivenom sera. Vaccines using pure antigens in alternative administration routes require the use of potent adjuvants and an effective antigen delivery system. Nanosystems are being investigated as delivery systems for therapeutic macromolecules. Chitosan, due to its properties, has been extensively investigated in nanocarriers formulations, particularly for genes and proteins. This study aimed to obtain chitosan nanoparticles (CNP) based on ionic gelation for the delivery of therapeutic proteins/peptides used in immunotherapy, as well as to evaluate the immunoadjuvant potential of these nanoparticles in the production of antivenom serums. CNP were obtained by ionic gelation, with an average size of 160 nm. Physicochemical characterization and evaluation of the release profile demonstrated that it is a modified release system. The stability of different systems was evaluated for 7 weeks, observing a greater stability of the systems associated with venoms. Experimental animals were immunized subcutaneously for 6 weeks with 100 uL snake venoms at different concentrations (5.0 or 10.0%), either encapsulated in CNP or associated with aluminum hydroxide (AH). The results demonstrate that the antibody titers observed for animals vaccinated with the studied nanosystems were equivalent or higher than those observed for animals vaccinated with HA. Further advantages of the nanosystems were to be less inflammatory, and to require smaller amounts of antigen to be administered, because it is a modified-release system, with potential application in anti-venom serum therapy.

Objetivos: Desenvolver e caracterizar hidrogéis de quitosana contendo capsaicinóides nanoencapsulados, bem como analisar o efeito das nanocápsulas e do veículo nos perfis de liberação dos capsaicinóides. Metodologia: As nanocápsulas foram obtidas (método de deposição interfacial do polímero préformado) utilizando Eudragit® RS100 e triglicerídeos do ácido cáprico/caprílico como parede polimérica e núcleo oleoso, respectivamente, e foram caracterizadas. Para determinação do teor e da taxa de associação da capsaicina e dihidrocapsaicina às nanocápsulas utilizou-se metodologia validada por CLAE-UV. As nanocápsulas contendo capsaicinóides foram incorporadas em hidrogel de quitosana. Para tanto, determinaram-se previamente as características reológicas e o hidrogel ideal para uso tópico. Através dos estudos de liberação in vitro, utilizando método de saco de diálise, foram obtidos os perfis de liberação dos fármacos a partir das nanocápsulas e destas incorporadas no veículo semissólido. Resultados e Discussão: As nanocápsulas apresentaram diâmetro médio de partícula de 153 ± 7nm (PDI < 0,2), potencial zeta de + 9,62 ± 1,48 mV, pH de 5,7 ± 0,1 e uma leve tendência à sedimentação, típica de suspensões. A nanoencapsulação dos capsaicinóides não provocou alterações nas características da formulação. O teor e a taxa de associação foram próximos a 100% para ambos capsaicinóides, considerando concentração de 0,5mg/mL de capsaicinoides na formulação. Foi possível obter um hidrogel de quitosana contendo nanocápsulas adequado para uso tópico. Previamente, observou-se uma grande influência da concentração de quitosana na consistência dos hidrogéis e um comportamento reológico pseudoplástico que não foi alterado pela adição das nanocápsulas. Observou-se uma liberação controlada devido à nanoencapsulação, de modo que dihidrocapsaicina foi liberada mais lentamente do que a capsaicina. Pode-se observar um retardo na liberação da capsaicina, quando as nanocápsulas foram incorporadas no hidrogel. Conclusões: Nanocápsulas estáveis e capazes de controlar a liberação dos capsaicinóides foram obtidas, sendo que tanto o núcleo oleoso quanto o polímero são responsáveis pelo controle da liberação. A formulação semissólida contendo nanocápsulas, obtida a partir do polímero quitosana, manteve a liberação controlada observada e apresentou adequadas características para aplicação tópica. / Purpose: To develop and characterize chitosan hydrogels containing nanoencapsulated capsaicin and dihydrocapsaicin, as well as to analyze the effect of the nanocapsulation and the vehicle on the in vitro release of the capsaicinoids. Methodology: Nanocapsules were obtained (interfacial deposition of the pre-formed polymer method) using Eudragit® RS100 and capric/caprylic triglycerids as the polymeric shell and oily core, respectively, and they were characterized. An HPLCUV validated method was used to determine the drug content and drug encapsulation efficiency. The nanocapsules containing capsaicinoids were incorporated in a chitosan hydrogel. Previously, the rheological properties and the most suitable hydrogel aiming the topical delivery were determined. By means of in vitro release experiments (dialyses bags), the release profiles of the capsaicinoids from the nanocapsules and the gel containing nanocapsules were obtained. Results and Discussion: The nanocapsule formulation presented an average diameter of 153 ± 7nm (PDI < 0.2), the zeta potential was +9.62 ± 1.48 mV, and the pH 5.7± 0.1. A slight tendency to sedimentation was observed, typical of suspensions. The drug encapsulation did not alter the formulation properties. The drug content and encapsulation efficiency were nearly 100% for both capsaicinoids, considering a drug amout of 0.5mg/mL of capsaicinoids in the formulation. A chitosan hydrogel containing nanocapsules were successfully obtanined. The chitosan concentration significantly influenced the consistence of the formulations, and the pseudoplastic behavior did not change after the nanocapsule incorporation. controlled release was observed due to nanoencapsulation, in a way that capsaicin released faster than dihydrocapsaicin. The release of capsaicin from the hydrogel containing nanocapsules presented a delay in comparison with the release from the nanocapsule suspension. Conclusions: Stable nanocapsules capable of controlling the capsaicinoids release were obtained. Both the oily core and the polymeric shell are responsible for the controlled release. The semi-solid formulation containing nanocapsules obtained with the polymer chitosan maintained the controlled release and presented suitable properties for cutaneous applications.