A obtenção da sílica vítrea pelo processo de sinterização por plasma pulsado (SPS), a partir de matérias-primas de diferentes estruturas (cristalina e amorfa) e diferentes granulometrias, foi investigada. Análises de difração de raios X, transmitância óptica, microscopia óptica e eletrônica de varredura, e medições de densidade foram realizadas nas amostras sinterizadas. Sílicas vítreas transparentes foram fabricadas a partir de pós de quartzo atingindo-se temperaturas finais entre 1450 e 1600°C, enquanto que nanopó e pó amorfo de sílica formaram consolidados transparentes com temperaturas máximas próximas de 1200° C. Taxas de aquecimento entre 40 e 150°C/min. foram utilizadas nas sinterizações, com tempos de processo menores que 40 minutos. As maiores taxas de aquecimento exigiram uma maior temperatura final para a fusão completa do material cristalino e causaram, de forma indireta, a presença de aglomerações de micro-bolhas nas amostras obtidas com o nanopó. Um gradiente radial de temperatura (decrescente do centro para as bordas) foi observado nos consolidados fabricados com os pós cristalinos, facilitando o processo de fechamento da porosidade aberta. A presença ou ausência de material não fundido e de bolhas nas amostras foram analisadas por difratogramas de raios X, microscopia óptica e medidas de densidade. A análise da transmitância indicou uma quantidade praticamente nula de grupos OH nos compactos sinterizados com os pós cristalinos e em torno de 20 ppm no caso dos sólidos fabricados com matéria-prima sol-gel. Amostras de nanopós de sílica dopada com titânia (~6% em massa) foram processadas com temperaturas finais de 1200 e 1400°C apresentando coloração azulada e negra, respectivamente, e aumento dos clusters de titânia para a temperatura mais elevada. A sinterização a uma temperatura em torno 1200°C mantida por apenas 4 minutos resultou na conversão completa da fase anatase para a fase rutilo da titânia. / The production of vitreous silica by the spark plasma sintering (SPS) process, starting from raw materials of different structures (crystalline and amorphous) and granulometry were investigated. Analysis of X-ray diffraction, optical transmittance, optical and scanning electron microscopy, and density measurements were performed on the sintered compacts. Transparent vitreous silica was fabricated from quartz powder at final temperatures ranging from 1450 and 1600°C while silica nanopowder and silica powder formed transparent compacts at temperatures around 1200°C. Heating rates between 40 and 150° C/min. were used in processes with durations smaller than 40 minutes. Higher heating rates demanded higher final temperatures to complete the fusion process and caused, indirectly, the formation of micro-bubbles agglomerations in the samples produced from the nanopowder. A radial gradient of temperature (decreasing from the center to the border) was observed at the compacts fabricated with the crystalline powders favoring the closure of the open porosity. The presence or the absence of non-fused material and bubbles in the samples was analyzed by X-ray diffraction, optical microscopy and density measurements. The transmittance analysis indicated an almost zero quantity of OH groups in the compacts sintered from crystalline powders and about 20 ppm in the solids fabricated from the sol-gel raw material. Nanopowder samples of silica titania (~6 wt % of titania) were processed with final temperatures of 1200°C and 1400°C presenting blue and black coloration, respectively, and an increase of the titania clusters for the highest temperature. The sintering at temperatures near 1200°C with a holding time of just 4 minutes caused the complete anatase-rutile conversion in titania.

The aim of the work was to design, manufacture, and characterize targeted multi-component dry powder aerosols of (non-destructive) mucolytic agent (mannitol), antimicrobial drug (tobramycin or azithromycin), and lung surfactant mimic phospholipids (DPPC:DPPG=4:1 in molar ratio). The targeted dry powder for inhalation formulation for deep lung delivery with a built-in rationale of specifically interfering several disease factors of chronic infection diseases in deep lungs such as cystic fibrosis, pneumonia, chronic bronchitis, and etc. The dry powder aerosols consisting of selected chemical agents in one single formulation was generated by using spray drying from organic solution. The physicochemical properties of multi-component dry powder inhaler (DPI) formulation were characterized by a number of techniques. In addition, the in vitro aerosol dispersion performance, storage stability test, and in vitro drug release of selected spray-dried (SD) multi-component systems were conducted. The physicochemical study revealed that multi-component aerosol particles possessed essential particle properties suitable for deep lung delivery. In general, the multi-component particles (typically 0.5 to 2 µm) indicated that the designed SD aerosol particles could potentially penetrate deep lung regions (such as respiratory bronchiolar and alveolar regions) by sedimentation and diffusion, respectively. The essential particle properties including narrow size distribution, spherical particle and smooth surface morphologies, and low water content (or water vapor sorption) could potentially minimize interparticulate interactions. The study of in vitro aerosol dispersion performance showed that majority of SD multi-component aerosols exhibited low values (less than 5µm) of MMAD, high values (approximately above 30% up to 60.4%) of FPF, and high values (approximately above 90%) of ED, respectively. The storage stability study showed that azithromycin–incorporated multi-component aerosol particles stored at 11 and 40% RH with no partial crystallization were still suitable for deep lung delivery. Compared to SD pure azithromycin particles, the azithromycin-incorporated multi-component particles exhibited an enhanced initial release. The targeted microparticulate and nanoparticulate multi-component dry powder aerosol formulations with essential particle properties for deep lung pulmonary delivery were successfully produced by using spray drying from organic solution. The promising experimental data suggest the multi-component formulations could be further investigated in in vivo studies for the purpose of commercialization.

SANCHO, Soraya de Oliveira. Estudo do potencial de resíduos de frutas tropicais para elaboração de suplemento alimentar probiótico. 2011. 203 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências, Programa de Pós-Graduação em Biotecnologia (Rede nordeste de Biotecnologia), Fortaleza-CE, 2011. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-05-27T16:26:58Z No. of bitstreams: 1 2011_tese_sosancho.pdf: 4193440 bytes, checksum: 7bf111a6bfc02a4e47da8ccf0c7de283 (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-05-27T16:27:24Z (GMT) No. of bitstreams: 1 2011_tese_sosancho.pdf: 4193440 bytes, checksum: 7bf111a6bfc02a4e47da8ccf0c7de283 (MD5) / Made available in DSpace on 2016-05-27T16:27:24Z (GMT). No. of bitstreams: 1 2011_tese_sosancho.pdf: 4193440 bytes, checksum: 7bf111a6bfc02a4e47da8ccf0c7de283 (MD5) Previous issue date: 2011 / The fruit processing industries produce large amounts of residues, which often do not receive adequate attention. This raw material has several constituents beneficial to health, which can be applied in the food industry in the development of new products. This study aimed to determine the feasibility of using agro-industrial residues such food supplements enriched with probiotic. Residues of pineapple (Ananas comosus L. Mer.), acerola (Malpighia glabra L.), cashew apple (Anacardium occidentale L.), guava (Psidium guajava L.), papaya (Carica papaya L.), mango (Mangifera indica L.) and sapodilla (Achras sapota L.) were evaluated. The physicochemical composition of the residues was determined with the analysis of total soluble solids, titratable acidity, pH, ascorbic acid, lipid, moisture, anthocyanins, water activity, protein, ash, total reducing sugars, total phenolics, antioxidant activity and mineral composition (Na, Mn, Ca, Fe, Mg, K, Zn and P) by the microwave digestion, digester block or ash techniques. The samples were analyzed by optical absorption spectrometry with inductively coupled plasma (ICP-OES). Microbial loads of the fruit residues (molds, yeasts, total coliforms and Escherichia coli) were also evaluated. Subchronic toxicity tests were performed with male Swiss mice by administration of extracts from fruit residues (C= 500 mg/ kg orally). The lethality bioassay against Artemia salina L., was conducted at 5,000, 1,000, 500, 100 and 10 mg/ mL concentrations from fruit residue extracts. In addition, tests were performed with the probiotic Lactobacillus casei NRRL B-442 grown in skim milk 10%, submitted to the lyophilization or atomization processes. The analytical results showed rich nutritional properties of the fruit residues and the acerola residue showed the highest values of total anthocyanins (60.83 mg/ 100 g), total phenolic compounds (173.30 mg EAG/ 100 g), ascorbic acid (170.73 mg/ 100 g) and antioxidant activity (48.21%). The microwave digestion procedure is the most suitable for minerals determination of fruit residues given the easiest and simplest analysis. The subchronic toxicity study, in the experimental conditions evaluated did not cause mortality or toxicity in male mice; however, additional studies are recommended. The lethality bioassay with Artemia salina L. indicated that acerola and cashew apple extracts showed biological activity, with LC50 values of 209.90 and 148.10 mg/ mL, respectively. In this study, no fungal contamination was detected, only the guava residue showed total coliforms and there was no evidence of E. coli in all samples, indicating no contamination of fecal origin. In tests with Lactobacillus casei, all counts obtained in fermented milk samples, submitted to drying processes, were within the limits required by legislation to be considered probiotic. Due to the nutritional properties, coupled with functional compounds and higher antioxidant activity, the acerola residue is proposed for the preparation of food supplement enriched with probiotic / As indústrias de processamento de frutas produzem uma grande quantidade de resíduos, que muitas vezes não recebem atenção adequada. Esta matéria-prima apresenta vários constituintes benéficos à saúde, que podem ser aplicados na indústria alimentícia no desenvolvimento de novos produtos. O presente trabalho teve como objetivo determinar a viabilidade de utilização de resíduos agroindustriais para a elaboração de suplemento alimentar enriquecido com probiótico. Foram analisados os resíduos de abacaxi (Ananas comosus L. Mer.), acerola (Malpighia glabra L.), caju (Anacardium occidentale L.), goiaba (Psidium guajava L.), mamão (Carica papaya L.), manga (Mangifera indica L.) e sapoti (Achras sapota L.). A composição físico-química dos resíduos foi determinada com as análises de sólidos solúveis totais, acidez total titulável, pH, ácido ascórbico, lipídios, umidade, antocianinas, atividade de água, proteínas, cinzas, açúcares redutores totais, compostos fenólicos totais, atividade antioxidante, além da composição de minerais (Na, Mn, Ca, Fe, Mg, K, Zn e P), a partir das técnicas de digestão por microondas, bloco digestor e cinzas. As amostras foram analisadas através de espectrometria de absorção óptica com plasma indutivamente acoplado (ICP-OES). Além disto, foram realizados os testes microbiológicos de bolores, leveduras, coliformes totais e Escherichia coli. Ensaios de toxicidade subcrônica foram realizados em camundongos Swiss machos, pela administração de soluções de extratos de resíduos de frutas (C= 500 mg/ kg, via oral). O bioensaio de letalidade frente à Artemia salina L., foi realizado em concentrações de 5.000, 1.000, 500, 100 e 10 µg/ mL de extratos de resíduos de frutas. Além disto, foram realizados testes com a bactéria Lactobacillus casei cultivada em leite desnatado 10%, submetido aos processos de secagem por liofilização e atomização. Os resultados analíticos indicaram ricas propriedades nutricionais em resíduos de frutas e o resíduo de acerola apresentou os maiores valores de antocianinas totais (60,83 mg/ 100 g), compostos fenólicos totais (173,30 mg EAG/ 100 g), ácido ascórbico (170,73 mg/ 100 g) e atividade antioxidante (48,21%). O processo de digestão por microondas foi o mais indicado para a determinação de minerais, devido à sensibilidade e facilidade de análise. O estudo de toxicidade subcrônica, nas condições experimentais utilizadas, não resultou em mortalidade ou toxicidade em camundongos machos, entretanto, estudos adicionais são recomendados. Os resultados para o bioensaio com Artemia salina L. indicaram que os extratos de acerola e caju apresentaram atividade biológica, com valores de LC50 iguais a 209,90 e 148,10 µg/ mL, respectivamente. Neste estudo, não foi detectada contaminação por bolores e leveduras; apenas a amostra de goiaba apresentou contaminação por coliformes totais e não houve evidência de E. coli em nenhuma amostra, indicando ausência de contaminação de origem fecal. Nos ensaios com Lactobacillus casei, todas as contagens obtidas nas amostras de leite fermentado, submetidos aos processos de secagem, se encontravam dentro do limite exigido pela legislação para ser considerado probiótico, podendo ser utilizado para a elaboração de suplementos alimentares. Devido às propriedades nutricionais, aliado aos compostos funcionais e atividade antioxidante mais elevada, o resíduo de acerola é proposto para elaboração de suplemento alimentar enriquecido com probiótico.

A obtenção da sílica vítrea pelo processo de sinterização por plasma pulsado (SPS), a partir de matérias-primas de diferentes estruturas (cristalina e amorfa) e diferentes granulometrias, foi investigada. Análises de difração de raios X, transmitância óptica, microscopia óptica e eletrônica de varredura, e medições de densidade foram realizadas nas amostras sinterizadas. Sílicas vítreas transparentes foram fabricadas a partir de pós de quartzo atingindo-se temperaturas finais entre 1450 e 1600°C, enquanto que nanopó e pó amorfo de sílica formaram consolidados transparentes com temperaturas máximas próximas de 1200° C. Taxas de aquecimento entre 40 e 150°C/min. foram utilizadas nas sinterizações, com tempos de processo menores que 40 minutos. As maiores taxas de aquecimento exigiram uma maior temperatura final para a fusão completa do material cristalino e causaram, de forma indireta, a presença de aglomerações de micro-bolhas nas amostras obtidas com o nanopó. Um gradiente radial de temperatura (decrescente do centro para as bordas) foi observado nos consolidados fabricados com os pós cristalinos, facilitando o processo de fechamento da porosidade aberta. A presença ou ausência de material não fundido e de bolhas nas amostras foram analisadas por difratogramas de raios X, microscopia óptica e medidas de densidade. A análise da transmitância indicou uma quantidade praticamente nula de grupos OH nos compactos sinterizados com os pós cristalinos e em torno de 20 ppm no caso dos sólidos fabricados com matéria-prima sol-gel. Amostras de nanopós de sílica dopada com titânia (~6% em massa) foram processadas com temperaturas finais de 1200 e 1400°C apresentando coloração azulada e negra, respectivamente, e aumento dos clusters de titânia para a temperatura mais elevada. A sinterização a uma temperatura em torno 1200°C mantida por apenas 4 minutos resultou na conversão completa da fase anatase para a fase rutilo da titânia. / The production of vitreous silica by the spark plasma sintering (SPS) process, starting from raw materials of different structures (crystalline and amorphous) and granulometry were investigated. Analysis of X-ray diffraction, optical transmittance, optical and scanning electron microscopy, and density measurements were performed on the sintered compacts. Transparent vitreous silica was fabricated from quartz powder at final temperatures ranging from 1450 and 1600°C while silica nanopowder and silica powder formed transparent compacts at temperatures around 1200°C. Heating rates between 40 and 150° C/min. were used in processes with durations smaller than 40 minutes. Higher heating rates demanded higher final temperatures to complete the fusion process and caused, indirectly, the formation of micro-bubbles agglomerations in the samples produced from the nanopowder. A radial gradient of temperature (decreasing from the center to the border) was observed at the compacts fabricated with the crystalline powders favoring the closure of the open porosity. The presence or the absence of non-fused material and bubbles in the samples was analyzed by X-ray diffraction, optical microscopy and density measurements. The transmittance analysis indicated an almost zero quantity of OH groups in the compacts sintered from crystalline powders and about 20 ppm in the solids fabricated from the sol-gel raw material. Nanopowder samples of silica titania (~6 wt % of titania) were processed with final temperatures of 1200°C and 1400°C presenting blue and black coloration, respectively, and an increase of the titania clusters for the highest temperature. The sintering at temperatures near 1200°C with a holding time of just 4 minutes caused the complete anatase-rutile conversion in titania.

Mauritia flexuosa Mart. (buriti) é uma espécie de palmeira que se encontra amplamente distribuída na América do Sul e Central. Com importância histórica no desenvolvimento do país, essa palmeira tem desempenhado relevante papel ambiental, econômico e sociocultural. O buriti fornece matéria-prima para múltiplas aplicações tais como alimentos, bebidas, cosméticos, mobiliário, artesanato, entre outros. As fibras retiradas das folhas jovens da palmeira, conhecidas popularmente como linho e borra de buriti, são muito empregadas em produtos de artesanato, os quais incorporam a memória cultural e artística das comunidades que os produzem. Os objetivos deste estudo foram: registrar o processo de extração, beneficiamento e produção artesanal com as fibras de buriti (linho e borra), junto à comunidade local (Barreirinhas-MA, Brasil) e em visitas técnicas a associações (São Luís-MA, Brasil); efetuar a caracterização físico-química têxtil dessas fibras e esteiras em estado natural e realizar a impregnação com resinas para verificar se ocorre melhoria nas propriedades desses materiais. Foi acompanhada e registrada a cadeia produtiva do artesanato com buriti e, com as gravações, fotografias e filmagens, foi realizado o vídeo intitulado Fibra de Buriti: da Folha ao Produto - Artesanato e Design. Os principais resultados dos testes tênseis, para o linho e borra de buriti, foram respectivamente: tenacidade na ruptura (cN/tex): 28,4±5,5 (CV=19,6%) e 18,0±6,3 (CV=34,9%); percentual de alongamento na ruptura (%): 8,3±0,5 (CV = 6,8%) e 5,0±0,8 (CV=15,5%); Módulo de Young (N/tex): 6,1±0,8 (CV=13,1%) e 6,0±1,6 (CV=25,9%). Esses valores para a fibra de linho sugerem potencial para processos de fiação, tecelagem e produção de compósitos, assim como em fibras de espécies de reconhecida empregabilidade têxtil. Os valores tênseis para a borra são inferiores aos relacionados aos da fibra de linho de buriti in natura. Os valores obtidos de regain das fibras de linho e borra de buriti in natura foram respectivamente 8,5% e 9%. Na microscopia de corte transversal, para a fibra de linho foi determinado diâmetro celular de 8,5 µm e, para a fibra de borra, diâmetro celular de 7,2 µm. Os testes de FTIR indicam uma grande semelhança de características químicas entre o linho e a borra de buriti. Assim, as principais diferenças notadas são devidas a diferenças de suas características físicas. Há indicação que os produtos feitos com o linho de buriti possam ser limpos através de processos brandos de lavagem doméstica sem danos significativos à sua estrutura. Por outro lado, a imersão em álcool provocou alterações aos materiais, contraindicando seu uso. De modo geral, a aplicação de resinas sobre os produtos feitos de fibras de buriti não implicou em melhorias consideráveis nas propriedades desses materiais, sendo seu uso recomendável somente em casos específicos. Assim, o presente estudo pretende ampliar o respeito com os saberes das comunidades locais que extraem e empregam essa fibra; aumentar as informações sobre a potencialidade da biodiversidade brasileira e a possibilidade de emprego da fibra de buriti na elaboração de soluções e novos produtos para aplicação em engenharia e design / Mauritia flexuosa Mart. (buriti) is a palm tree species which is widely distributed in South and Central America. Presenting historical importance in the development of the country, this palm has played a significant environmental, economic and socio-cultural role. Buriti provides raw material for multiple applications such as food, beverages, cosmetics, furniture, handicrafts, among others. The fibers removed from the young leaves of the palm tree, popularly known as buriti linen and draff, are very much employed in handicraft products, which incorporate the cultural and artistic memory of the communities that produce them. The objectives of this study were: to record the process of extraction, processing and handicraft production with buriti fibers (\'linen\' and draff), together to local community (Barreirinhas-MA, Brazil) and technical associations visits (São Luís-MA, Brazil); to perform the textile physicochemical characterization of these fibers and mats in natural state and carry out the impregnation with resins in order to investigate the possibility of improvement in the properties of these materials. The handicraft production chain with buriti was monitored and recorded and with the recordings, photos and films, was made the video entitled \"Buriti fiber: from leaf to product Handicraft and Design\". The main results of tensile tests for \'linen\' and \'draff\' of buriti, were respectively: tenacity at break (cN/tex): 28.4±5.5 (CV=19.6%) and 18.0±6.3 (CV=34.9%); percentage elongation at break (%): 8.3±0.5 (CV=6.8%) and 5.0±0.8 (CV=15.5%); Young\'s Modulus (N/tex): 6.1±0.8 (CV=13.1%) and 6.0±1.6 (CV=25.9%). These values for linen fiber suggest the potential for spinning, weaving and production of composites processes, as well as fiber species of recognized textile employment. The tensile values for draff fiber are lower than related to the \'linen\' buriti fiber in natura. The values obtained from regain of the \'linen\' and \'draff\' fibers of buriti in natura were respectively 8.5% and 9%. In the cross microscopy for linen fiber \'flax\' was determined the cell diameter of 8.5 µm and for the draff fiber, cell diameter of 7.2 µm. FTIR tests indicate a strong similarity between the chemical characteristics of linen and draff of buriti. Thus, the main noticeable differences are due to differences in their physical characteristics. There is indication that the products made with the buriti linen could be cleaned by gentle home laundering processes without significant damage to its structure. Moreover, the immersion in alcohol caused changes to the materials, contraindicating their use. Generally, the application of resins on products made of buriti fibers did not result in significant improvements in the properties of these materials, and its employment is recommended only in specific cases. Therefore, this study intends to increase the compliance with the knowledge of local communities that draw and employ this fiber; to increase information about the potential of Brazilian biodiversity and the possibility of buriti fiber use in the elaboration of solutions and new products for application in engineering and design

[pt] O conhecimento do comportamento geológico-geotécnico de solos formados em ambientes tropicais, em particular na região Amazônica, ainda é escasso tanto no país quanto no exterior. Visando contribuir para tal, o presente trabalho apresenta resultados de uma extensa campanha experimental envolvendo ensaios de laboratório em amostras amolgadas e indeformadas coletadas nos platôs dissecados do município de Oriximiná, localizado no norte do Pará, Brasil. O material foi extraído do horizonte mais inferior do perfil de solo local, chamado de argila variegada, assim definida por apresentar uma coloração variada (do vermelho ao branco). Tal tipo de solo argiloso, não saturado, constitui o principal material de fundação dos platôs de exploração e de armazenamento de rejeitos oriundos da atividade mineradora da região sendo, portanto, relevante um entendimento cientificamente embasado acerca de seu comportamento sob o ponto de vista de engenharia. Para subsidiar um melhor entendimento desse comportamento, o trabalho apresenta resultados de ensaios físicos (ensaios geotécnicos básicos tais como de granulometria, densidade relativa dos grãos e limites de Atterberg); análises químicas total e parcial, pH e de matéria orgânica; ensaios mineralógicos por difração de raios X e utilizando lupa binocular; ensaios de retenção de umidade (papel filtro) e ensaios de micro-morfologia dos solos, como de porosimetria, tomografia computadorizada e microscopia eletrônica de varredura (MEV). Os resultados obtidos sugerem que este solo é de origem residual, essencialmente composto por caulinita, com traços de gibbsita e cimentações ferruginosas, com uma microestrutura que pode explicar um caráter fortemente anisotrópico de permeabilidade, ajudando a justificar o que é evidenciado em resultados de investigações de campo efetuadas na área. / [en] Knowledge of the geological-geotechnical behaviour of soils formed in tropical environments, particularly in the Amazon region, is still scarce both in Brazil and abroad. In order to understand this behaviour, an extensive experimental campaign was carried out with laboratory tests on disturbed and undisturbed samples collected from the dissected plateaus of the municipality of Oriximiná, located in the north of Pará, Brazil. The material was extracted from the lowest horizon of the local lithological profile, called variegated clay, characterized by its varied colour (from red to white). This type of clayey soil constitutes the main foundation material of the plateaus for exploration and storage of tailings from the mining activity in the region, which demands a scientifically based understanding of its behaviour from an engineering point of view. Therefore, the work presents results of physical tests, including measurements of material suction through characteristic retention curves, chemical tests of grain composition, pH and presence of organic matter, mineralogical tests of X-ray diffraction and binocular observation, and soil micromorphology tests, such as porosimetry, computed tomography and scanning electron microscopy (SEM). The results suggest that this soil is of residual origin, essentially composed of kaolinite, with traces of gypsum and ferruginous cementations, with a microstructure that can explain a strongly anisotropic character of permeability evidenced by results of field investigations carried out in the area.

O presente estudo teve como objetivo obter e caracterizar complexos binários e ternários de benznidazol (BNZ) com ciclodextrinas e polímeros hidrossolúveis com a finalidade de melhorar a solubilidade do fármaco. Efetuou-se a caracterização físico-química do fármaco avaliando-se solubilidade, calorimetria exploratória diferencial (DSC), termogravimetria (TGA), investigação de novas formas cristalinas e a definição de parâmetros para o ensaio de dissolução intrínseca. Posteriormente, esses dados foram utilizados como referência nos estudos de caracterização dos complexos de inclusão. Os complexos binários utilizaram as ciclodextrinas naturais αCD, βCD e γCD, e os ternários a βCD e HPβCD e adição de 1,0% de polímeros hidrossolúveis (povidona e copovidona). Os complexos foram secos em estufa e adicionalmente dois métodos de preparo co-evaporação e liofilização foram empregados para comparação e escolha do mais adequado. O estudo de caracterização dos complexos foi realizado através do método de solubilidade de fases, DSC e TGA. A constante de estabilidade, a eficiência de complexação e solubilidade sugeriram maior interação do fármaco com a βCD. Nos complexos ternários, a utilização de copovidona foi mais efetiva que a povidona. Houve aumento da solubilidade quando os complexos foram preparados pelo método de liofilização. A melhor solubilidade foi alcançada pelos complexos BNZ:βCD (0,84 mg/mL) e BNZ:βCD:copovidona (0,86 mg/mL) preparados pelo método de liofilização. / The present study was aimed to obtain and characterize binary and ternary complexes of benznidazole (BNZ) with cyclodextrins and water-soluble polymers with the purpose to improve the solubility of drug. It was performed the physicochemical characterization of BNZ by differential scanning calorimetry (DSC), thermogravimetry (TGA), investigation of new crystalline forms and the definition of parameters for the intrinsic drug dissolution test of intrinsic dissolution. Subsequently, these informations were used as reference in the studies of characterization of the inclusion complexes. The binary complexes were prepared with the cyclodextrins αCD, βCD and γCD and the ternary with βDC and HPβCD and addition of 1.0% of water-soluble polymers (povidone and copovidone). The complexes were dried in tray drayer and additionally two methods of preparation coevaporation and lyophilization were employeed for comparison and the best was selected. The characterization of the complexes was carried out by phase-solubility method, DSC and TGA. The constant of stability, the efficiency of complexation and solubity suggested higher interaction of the drug with the βCD. In the ternary complexes, the use of copovidone was more effective in the solubility than to povidone. There was an increased of solubility when the complexes were prepared by lyophilization. To best solubility was achieved by the complexes BNZ:βCD (0.84 mg/ml) and BNZ:βCD:copovidone (0.86 mg/ml) prepared by lyophilization method.

O presente estudo teve como objetivo obter e caracterizar complexos binários e ternários de benznidazol (BNZ) com ciclodextrinas e polímeros hidrossolúveis com a finalidade de melhorar a solubilidade do fármaco. Efetuou-se a caracterização físico-química do fármaco avaliando-se solubilidade, calorimetria exploratória diferencial (DSC), termogravimetria (TGA), investigação de novas formas cristalinas e a definição de parâmetros para o ensaio de dissolução intrínseca. Posteriormente, esses dados foram utilizados como referência nos estudos de caracterização dos complexos de inclusão. Os complexos binários utilizaram as ciclodextrinas naturais αCD, βCD e γCD, e os ternários a βCD e HPβCD e adição de 1,0% de polímeros hidrossolúveis (povidona e copovidona). Os complexos foram secos em estufa e adicionalmente dois métodos de preparo co-evaporação e liofilização foram empregados para comparação e escolha do mais adequado. O estudo de caracterização dos complexos foi realizado através do método de solubilidade de fases, DSC e TGA. A constante de estabilidade, a eficiência de complexação e solubilidade sugeriram maior interação do fármaco com a βCD. Nos complexos ternários, a utilização de copovidona foi mais efetiva que a povidona. Houve aumento da solubilidade quando os complexos foram preparados pelo método de liofilização. A melhor solubilidade foi alcançada pelos complexos BNZ:βCD (0,84 mg/mL) e BNZ:βCD:copovidona (0,86 mg/mL) preparados pelo método de liofilização. / The present study was aimed to obtain and characterize binary and ternary complexes of benznidazole (BNZ) with cyclodextrins and water-soluble polymers with the purpose to improve the solubility of drug. It was performed the physicochemical characterization of BNZ by differential scanning calorimetry (DSC), thermogravimetry (TGA), investigation of new crystalline forms and the definition of parameters for the intrinsic drug dissolution test of intrinsic dissolution. Subsequently, these informations were used as reference in the studies of characterization of the inclusion complexes. The binary complexes were prepared with the cyclodextrins αCD, βCD and γCD and the ternary with βDC and HPβCD and addition of 1.0% of water-soluble polymers (povidone and copovidone). The complexes were dried in tray drayer and additionally two methods of preparation coevaporation and lyophilization were employeed for comparison and the best was selected. The characterization of the complexes was carried out by phase-solubility method, DSC and TGA. The constant of stability, the efficiency of complexation and solubity suggested higher interaction of the drug with the βCD. In the ternary complexes, the use of copovidone was more effective in the solubility than to povidone. There was an increased of solubility when the complexes were prepared by lyophilization. To best solubility was achieved by the complexes BNZ:βCD (0.84 mg/ml) and BNZ:βCD:copovidone (0.86 mg/ml) prepared by lyophilization method.

La pollution atmosphérique constitue de nos jours un enjeu sociétal majeur, tant pour ses conséquences néfastes sur la santé humaine que sur l'environnement. L'objectif général de ce présent travail était de déterminer le niveau de la pollution atmosphérique dakaroise, extérieure et intérieure, et d'évaluer son impact sanitaire au sein de la population urbaine. Les particules fines (PM₂.₅) et une fraction plus grossière (PM>₂.₅) échantillonnées sur un site urbain de Dakar (HLM), caractérisées par de fortes émissions du trafic routier, ont été comparées aux particules échantillonnées dans une zone rurale, Toubab Dialaw, située à environ 40 kms de Dakar. Les caractéristiques physicochimiques des échantillons ont révélé que les particules différaient par leurs propriétés physiques (surface) et chimiques (en termes de CHN, métaux, ions, paraffines, COV et HAP) de 65 à 75 % plus élevées dans les échantillons urbains. Selon les différentes sources et les différentes propriétés physiques et chimiques, la réponse inflammatoire (TNF-α, IL-1β, IL-6, IL-8) et les dommages oxydatifs (protéines carbonylées totales et 8-OHdG) se sont révélés plus importants dans les cellules bronchiques BEAS-2B exposées aux particules urbaines. La campagne de mesure de la qualité de l'air a montré que l'intérieur du bus était plus pollué en PM₁₀, CO, CO₂ et NO que le marché et les sites intérieurs urbains et ruraux. La comparaison de la qualité de l'air entre les sites intérieurs et extérieurs a révélé que, particulièrement dans les zones urbaines, la qualité de l'air intérieur pouvait être moins bonne que celle des sites extérieurs correspondants. Le suivi de l'exposition individuelle aux polluants a montré que les ménagères de la zone urbaine et rurale étaient plus exposées que les professionnels à la pollution de l'air, confirmant les observations précédentes d'un niveau d'exposition potentiellement plus élevé des polluants dans l'environnement intérieur. Cependant, il convient de tenir compte du niveau d'exposition des commerçants et des conducteurs d'autobus résultant de l'échappement du trafic avec des véhicules souvent anciens, mal entretenus et non contrôlés, en raison des niveaux élevés de polluants gazeux rapportés ici. / Air pollution is nowadays a major societal challenge, as much for its harmful consequences on human health as on the environment. The general objective of this work was to determine the level of Dakar air pollution, outdoor and indoor, and to assess its health impact in the urban population. Fine particles (PM₂.₅) and a coarser fraction (PM>₂.₅) sampled at an urban site in Dakar (HLM), characterized by high road traffic emissions, were compared with particles sampled at a rural area, Toubab Dialaw located about 40 km from Dakar. The physicochemical characteristics of samples revealed that PMs differ for their physical (surface area) and chemical properties (in terms of CHN, metals, ions, paraffins, VOCs and PAHs) that were 65 to 75 % higher in urban samples. In accordance with the different sources and different physical and chemical properties, the inflammatory response (TNF-α, IL-1β, IL-6, IL-8) and the oxidative damage (total carbonylated proteins and 8-OHdG) were found higher in bronchial BEAS-2B cells exposed to urban PMs. The air quality measurement campaign showed that the bus interior was more polluted with PM₁₀, CO, CO₂ and NO than the market and the urban and rural indoor sites. The comparison of air quality between indoor and outdoor sites revealed that, particularly in urban areas, indoor air quality may be worse than the corresponding outdoor one. Monitoring individual exposure to pollutants showed that housewives in urban and rural sites were more exposed than professionals to air pollution, confirming previous observations of potential higher individual exposure level to pollutants in indoor environment. However, exposure level of traders and bus drivers that would result from the exhaust of traffic with often old, poorly maintained and uncontrolled vehicles has to be taken into consideration due the higher levels of gaseous pollutants here reported.

Bien que dits « inoxydables », les aciers inox peuvent être sujets à diverses formes decorrosion localisée telles que la piqûration. La formation de piqûres, nuisible à l’aspect et à l’intégritéstructurelle du matériau, est notamment contrôlée par les propriétés du film passif protecteur qui seforme à la surface des inox. De nombreuses études ont été menées sur les mécanismes de piqûration desurfaces modèles préparées au laboratoire. Cette thèse, au contraire, étudie les relations entre lespropriétés physico-chimiques et électroniques, d’une part, et la résistance à la corrosion par piqûres,d’autre part, de films passifs formés sur des inox par des finis de surfaces industriels.Les propriétés des films passifs ont été caractérisées par des méthodes variées, utiliséesclassiquement ou de façon plus originale : multi-piqûres et transitoires électrochimiques pour lapropriété d’usage, XPS et SDL pour la chimie de surface, spectroscopie d’impédance électrochimique,chrono-ampérométrie et photoélectrochimie pour les propriétés semi-conductrices des films.Il a été montré que la résistance à la piqûration des finis industriels pouvait valablement êtredéterminée par la méthode des transitoires électrochimiques et par la multi-piqûres, utiliséesauparavant pour les seules surfaces modèles. Par ailleurs, l’analyse comparée des résultats depiqûration et de ceux d’XPS et SDL a mis en évidence que la composition chimique des films passifsne suffit pas à rendre compte des différences de résistance à la piqûration des différents finisindustriels testés. En revanche, l’analyse des propriétés semi-conductrices des différents films passifs apermis de proposer des explications à ces écarts de comportements en corrosion localisée, confirmantque structure et taux de défauts du film passif sont deux paramètres clef de la résistance à la corrosionpar piqûres des films passifs.Enfin, une amélioration du comportement en piqûration des surfaces industrielles a pu êtremise en évidence, soit après un traitement court de ces dernières en milieu nitrique acide, soit àl’application aux échantillons d’un balayage en potentiel en milieu sulfate neutre. / Stainless steels can suffer localized corrosion like pitting corrosion which can damage thestructural integrity of the material. The pit formation is mainly controlled by properties of theprotective layer formed on the stainless steel surface, which is called passive film. Many studies haveexamined pitting mechanism on model surface prepared in the laboratory. This work is dedicated tostudy the relations between physicochemical and electronic properties of industrially processedpassive films and their pitting corrosion resistance.The properties of passive films have been characterized with several methods which can beconventional or in a more innovative way: multi-pitting statistics and electrochemical noise for the useproperty, XPS and SDL for the surface chemistry, electrochemical impedance spectroscopy,chronoamperometry and photo-electrochemistry for semi-conductive properties of the passive films.Multi-pitting statistics and electrochemical transients which were usually used on modelsurfaces have been shown to be accurate for the evaluation of the pitting resistance of industrialsurface finishing samples. Furthermore, the comparison of the results of pitting resistance and of XPSand SDL analyses has shown that the chemical composition of passive films is not sufficient to explainthe difference of pitting resistance behavior among tested industrial passive films. However, the semiconductiveproperties characterizations are able to explain these differences of localized corrosionresistance. They confirm that structuration and defect level are two key parameters of pitting resistanceproperties of passive films.At last, this study highlighted that the pitting resistance of industrial passive films can beimproved by a short nitric acid treatment or by sweep voltammetry in neutral sulfate medium.