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The first project focused on the preparation, characterization, and application of dual emission quantum dot encoded mesoporous silica microparticles. The quantum dots were added in precisely controlled ratios and were stably encapsulated within the pores of the silica. Several experiments were performed to test the superior stability of the quantum dot-silica composites over dye-loaded silica particles. The composite particles exhibited very high fluorescence, were functionalized with antibodies, and were used as signal transducers for the detection of a protein expressed by breast cancer cells. The second project focused in more detail on the detection capabilities of the quantum dot-silica composites. Three different types of quantum dot-silica composites were prepared. Each type was loaded with a separate type of quantum dot with distinct emission wavelengths and was functionalized with separate antibodies for detection of three different breast cancer biomarkers. These three composite sensors were used together for the simultaneous detection of each of the breast cancer markers. The initial strategy utilized the direct detection method in which the antigen is nonspecifically adsorbed to a glass plate. An improved second strategy was more sensitive and used a capture antibody which was covalently bound to a glass plate to immobilize the antigen. The third project focused on the preparation and application of magnetic, fluorescent human serum albumin nanoparticle composites. A fluorescent drug analogue and iron oxide nanoparticles were encapsulated into 100 nm human serum albumin nanoparticles. The advantage of these composite particles is that they could be used as a theranostic tool which could target, detect, and treat diseased tissue in a single application. Release of the drug analogue from the nanocomposites was achieved by addition of proteolytic enzymes that are expressed or overexpressed in cancer cells. The temporal release of the fluorescent drug analogue was measured as a function of enzyme concentration. The amount of drug released was directly proportional to enzyme concentration.

O microrreator faz parte de conjunto de dispositivos de uma nova e promissora tecnologia, que podem ser chamados de micro fabricados, atuante em campos como a da química, biológica, farmacêutica, engenharia química e biotecnologia. Trata-se de um dispositivo que possibilita reação química, tais como os reatores convencionais, mas com dimensões menores, com canais na escala micrométrica. A tecnologia de miniaturização de dispositivos para reações químicas vem se expandindo promovendo uma importante evolução, com microssistemas que abrange dispositivos mais eficazes, com configuração e geometrias específicas e menor consumo de energia, onde reações com elevadas taxas de transporte podem ser usadas para muitas finalidades diferentes, tais como, reações rápidas, mistura, reações sensíveis à temperatura, temperatura de homogeneização, ou até mesmo precipitação de nano partículas. Devido sua escala ser extremamente reduzida em relação à escala macro, oferecem um sistema que permite uma investigação do processo em um curto espaço de tempo, sendo muito útil para o rastreio de substratos, enzimas, condições de reação, bem como a determinação de parâmetros cinéticos. O presente trabalho teve por objetivo estudar a biodegradação enzimática de 2,4,6-Triclorofenol, com a utilização das enzimas Lacase e Soybean Peroxidase em microrreator da Syrris com volume de 250 ?l, que permite o estudo de cinéticas muito rápidas. Para as análises de degradação utilizou-se duas enzimas, a Lacase em concentrações de 0,05; 0,1 e 0,2 mg/ml; e a Soybean Peroxidase em concentrações de 0,0005; 0,001 e 0,002 mg/ml com a adição de Peróxido de Hidrogênio. Através dos ensaios realizados obteve-se dados experimentais da reação enzimática, possibilitando a verificação da taxa inicial de reação e sua cinética. Posteriormente, realizou-se as análises em simulação utilizando os dados experimentais, que através de um sistema de EDOs estimando inicialmente as constantes cinéticas k1, k2 e k3 usando a ferramenta ESTIMA, onde apresentaram duas respostas, uma resposta típica de mínimos quadrados, e a outra resposta que a velocidade inicial, que foi melhor representada pelos parâmetros obtidos. O método empregado na degradação do substrato, o microrreator mostrou-se eficiente, permitindo a detecção de baixo consumo de substrato para a determinação da taxa inicial, em curto tempo de residência. Perante os ensaios realizados com Lacase e Soybean Peroxidase, o microrreator é também um equipamento eficaz na repetitividade e na reprodutibilidade dos dados obtidos em diferentes concentrações. / The microreactor is part of a set of devices in a new and promising technology, which can be called micro manufactured, active in fields such as chemical, biological, pharmaceutical, chemical engineering and biotechnology. It is a device that enables chemical reactions, such as conventional reactors, but with smaller dimensions, in the micrometer scale channels. Miniaturization technology devices for chemical reactions is expanding promoting an important development, with microsystems covering most effective devices, configuration and specific geometries and lower power consumption, where reactions with high transportation fees can be used for many different purposes such as fast reactions, mixing, temperature sensitive reactions, homogenization temperature or even precipitation of nanoparticles. Because of its scale is greatly reduced compared to the macro scale, provide a system which allows an investigation of the process in a short time, being very useful for screening for substrates, enzymes, reaction conditions, and the determination of kinetic parameters. One of the advantages of using microreactors is that this equipment requires small amounts of reagents for performing a catalytic reaction of action, and is very important when dealing with enzyme as a catalyst. This study aimed to study the enzymatic biodegradation of 2,4,6-Trichlorophenol with the use of laccase and Soybean Peroxidase enzymes in microreactor Syrris with volume of 250 ?l, which allows the study of very fast kinetics. For degradation analyzes were used two enzymes, laccase concentrations of 0.05; 0.1 and 0.2 mg / ml; and Soybean peroxidase at concentrations of 0.0005; 0.001 and 0.002 mg / ml with the addition of Hydrogen Peroxide. Through trials was obtained experimental data from enzyme reaction, allowing the verification of the initial reaction rate and its kinetics. Later, there was the analysis simulation using the experimental data, which through a system of ODEs initially estimating the rate constants k1, k2 and k3 using the ESTIMA tool, which had two answers, a typical response of least squares, and another answer to the initial rate, which was best represented by the parameters obtained. The method used in substrate degradation, the microreactor was efficient, allowing low substrate consumption detection for determining the initial rate in the short residence time. Before the tests with Laccase and Soybean Peroxidase, the microreactor is also an effective equipment in the repeatability and reproducibility of the data obtained at different concentrations.

O microrreator faz parte de conjunto de dispositivos de uma nova e promissora tecnologia, que podem ser chamados de micro fabricados, atuante em campos como a da química, biológica, farmacêutica, engenharia química e biotecnologia. Trata-se de um dispositivo que possibilita reação química, tais como os reatores convencionais, mas com dimensões menores, com canais na escala micrométrica. A tecnologia de miniaturização de dispositivos para reações químicas vem se expandindo promovendo uma importante evolução, com microssistemas que abrange dispositivos mais eficazes, com configuração e geometrias específicas e menor consumo de energia, onde reações com elevadas taxas de transporte podem ser usadas para muitas finalidades diferentes, tais como, reações rápidas, mistura, reações sensíveis à temperatura, temperatura de homogeneização, ou até mesmo precipitação de nano partículas. Devido sua escala ser extremamente reduzida em relação à escala macro, oferecem um sistema que permite uma investigação do processo em um curto espaço de tempo, sendo muito útil para o rastreio de substratos, enzimas, condições de reação, bem como a determinação de parâmetros cinéticos. O presente trabalho teve por objetivo estudar a biodegradação enzimática de 2,4,6-Triclorofenol, com a utilização das enzimas Lacase e Soybean Peroxidase em microrreator da Syrris com volume de 250 ?l, que permite o estudo de cinéticas muito rápidas. Para as análises de degradação utilizou-se duas enzimas, a Lacase em concentrações de 0,05; 0,1 e 0,2 mg/ml; e a Soybean Peroxidase em concentrações de 0,0005; 0,001 e 0,002 mg/ml com a adição de Peróxido de Hidrogênio. Através dos ensaios realizados obteve-se dados experimentais da reação enzimática, possibilitando a verificação da taxa inicial de reação e sua cinética. Posteriormente, realizou-se as análises em simulação utilizando os dados experimentais, que através de um sistema de EDOs estimando inicialmente as constantes cinéticas k1, k2 e k3 usando a ferramenta ESTIMA, onde apresentaram duas respostas, uma resposta típica de mínimos quadrados, e a outra resposta que a velocidade inicial, que foi melhor representada pelos parâmetros obtidos. O método empregado na degradação do substrato, o microrreator mostrou-se eficiente, permitindo a detecção de baixo consumo de substrato para a determinação da taxa inicial, em curto tempo de residência. Perante os ensaios realizados com Lacase e Soybean Peroxidase, o microrreator é também um equipamento eficaz na repetitividade e na reprodutibilidade dos dados obtidos em diferentes concentrações. / The microreactor is part of a set of devices in a new and promising technology, which can be called micro manufactured, active in fields such as chemical, biological, pharmaceutical, chemical engineering and biotechnology. It is a device that enables chemical reactions, such as conventional reactors, but with smaller dimensions, in the micrometer scale channels. Miniaturization technology devices for chemical reactions is expanding promoting an important development, with microsystems covering most effective devices, configuration and specific geometries and lower power consumption, where reactions with high transportation fees can be used for many different purposes such as fast reactions, mixing, temperature sensitive reactions, homogenization temperature or even precipitation of nanoparticles. Because of its scale is greatly reduced compared to the macro scale, provide a system which allows an investigation of the process in a short time, being very useful for screening for substrates, enzymes, reaction conditions, and the determination of kinetic parameters. One of the advantages of using microreactors is that this equipment requires small amounts of reagents for performing a catalytic reaction of action, and is very important when dealing with enzyme as a catalyst. This study aimed to study the enzymatic biodegradation of 2,4,6-Trichlorophenol with the use of laccase and Soybean Peroxidase enzymes in microreactor Syrris with volume of 250 ?l, which allows the study of very fast kinetics. For degradation analyzes were used two enzymes, laccase concentrations of 0.05; 0.1 and 0.2 mg / ml; and Soybean peroxidase at concentrations of 0.0005; 0.001 and 0.002 mg / ml with the addition of Hydrogen Peroxide. Through trials was obtained experimental data from enzyme reaction, allowing the verification of the initial reaction rate and its kinetics. Later, there was the analysis simulation using the experimental data, which through a system of ODEs initially estimating the rate constants k1, k2 and k3 using the ESTIMA tool, which had two answers, a typical response of least squares, and another answer to the initial rate, which was best represented by the parameters obtained. The method used in substrate degradation, the microreactor was efficient, allowing low substrate consumption detection for determining the initial rate in the short residence time. Before the tests with Laccase and Soybean Peroxidase, the microreactor is also an effective equipment in the repeatability and reproducibility of the data obtained at different concentrations.

A recent focus in the biomedical engineering field has been on developing models of in-vivo tissue responses to help better predict aortic wall mechanics, through numerical methods and simulation, towards improved prediction of aortic wall rupture. The structural influence of both collagen and elastin, integral components within the aortic wall, has been studied and is largely understood, but the contribution of glycosaminoglycans (GAGs) is still unclear. While it has been suggested that the swelling properties of GAGs may participate in the regulation of residual stresses in the aortic wall, whether or not GAGs affect the mechanical properties of the aortic wall is completely unknown. The present study was divided into two experiments: Experiment 1 (n=9) utilized planar biaxial testing to characterize arterial wall mechanics in native porcine aortas. The results of Experiment 1 highlight: (i) decreased tissue thickness moving distally, away from the heart; (ii) increased stiffness from the ascending aorta to the thoracic descending aorta; (iii) no difference in morphometry or stress-strain behaviour between samples excised from the anterior, posterior, and/or left and right lateral walls. Experiment 2 (n=8) employed identical testing parameters to characterize partial and fully enzymatically GAG-depleted tissue, to determine the influence of this macromolecule on aortic wall mechanics. The results of Experiment 2 highlight: (i) GAG content in the porcine aorta does not affect tissue mechanical properties measured from biaxial testing; (ii) enzymatic removal of GAGs does not influence morphometric parameters, including thickness and area. These findings will contribute to improving the fundamental understanding of aortic tissue mechanics by helping to determine the relationship between spatial dependency and mechanical response, and the relationship between individual aortic wall constituents and the overall mechanical behaviour of the aorta.

Most marketed formulations for treating anterior ocular conditions are topical, with conventional eyedrops representing the most utilized modality. However, due to the natural clearance mechanisms of the eye, less than 5% of an applied dose remains bioavailable following administration. To overcome the shortcomings associated with conventional eyedrops, a series of enzymatically degradable, mucoadhesive thermogels were developed. Thermogels can be applied as a solution, like a conventional eyedrops, but gel against the heat of eye. To avoid obstructing vision, these thermogels were designed to be instilled within the inferior fornix of the eye. In these studies, the base thermogelling polymer (pNAM) was crosslinked with the natural polymer chitosan. Not only does crosslinking strengthen the typically weak thermogels, but chitosan can be enzymatically degraded by lysozyme, the highest concentration protein found in tear fluid. Therefore, the developed thermogels can be applied to the inferior fornix and degrade over multiple days. A limitation of applying materials to the inferior fornix is they tend to be poorly retained. To anchor the developed thermogels within the inferior fornix, the mucoadhesive properties were tailored based on the chitosan utilized as well as the inclusion of a disulfide monomer capable of covalently bonding with the natural mucosal layer covering the surface of the eye. The disulfide bridging monomer could be further conjugated with therapeutic components which were released as a function of mucosal interaction. Conjugates investigated included cysteamine for treating cystinosis, n-acetyl cysteine for treating dry eye, the adhesion peptide RGDC as a model peptide/protein, and polyethylene glycol for modulating material properties. The release of the drugs Ketotifen Fumarate, for treating allergic conjunctivitis, and atropine, for treating myopia, were also investigated. The safety of the developed thermogels were studied both in vivo and extensively in vitro utilizing both rat and rabbit models. / Dissertation / Doctor of Philosophy (PhD) / Topical eyedrops are the most utilized treatment option for the vast majority of ocular diseases. However, eyedrops are largely ineffective with less than 5% of an applied dose reaching the desired cite of action. Therefore, eyedrops need to be frequently reapplied. To overcome these limitations, an eyedrop was developed which can be applied as a liquid but gels against the heat of the eye. This gel allows for prolonged drug release over multiple days, greatly increasing drug efficacy as well as patient comfort and compliance. To prevent obstructing vision, these gels can be applied under the lower eyelid. To keep these gels retained under the lower eyelid, they were designed to anchor to the natural mucus layer which covers the surface of eye. The developed eyedrops represent a significant advancement in ocular care; bettering the convenience, comfort, and effectiveness for patients of a topical formulation compared to traditional eyedrops.

Cell biology is a branch of science with a seemingly infinite abundance of interesting phenomena which are essential to our understanding of life and which may potentially drive the development of technology that improves our lives. Among the open ended questions within the field, an understanding of how gene networks are affected by limited cellular components is both broad and rich with interest. Common to all cellular systems are enzymes which perform many tasks within cells without which organisms could not remain healthy. Here are presented several explorations of enzymatic processing as well as a tool constructed for this purpose. More specifically, these works consider the effect of coupling of gene networks via competition for enzymes found within the cell. It is shown that a limitation on the number of available enzymes permits the formation of bottlenecks which drastically affect molecular dynamics within cells. These effects potentially afford cell behaviors that in part explain the impressive robustness of life to constantly fluctuating environments. / Ph. D.

Made available in DSpace on 2017-07-10T19:24:46Z (GMT). No. of bitstreams: 1 Dayane Cristina da Rocha.pdf: 1452913 bytes, checksum: 15c01c66c71278c9a56f1e0eb396f63c (MD5) Previous issue date: 2010-07-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Biodiesel is a derived fuel from renewable biomass that can substitute partially or totally the fossil fuel. The production process of the biodiesel is composed by the following stages: raw material preparation, transesterification reaction, phases separation, alcohol recovery and dehydration, glycerin destillation and purification of the renewable fuel, resulting in glycerin as a by-product and purification wastewater. The formed wastewater during the stage of purification presents high concentration of oils and greases, presenting potential to contaminate bodies of water. One of the treatment proposals of this residue is the enzymatic hydrolysis use by lipases for removal of oils and greases. Due the specificity of lipases and its large technological application, it appears that it is necessary to search new microorganisms producers of this enzyme, with specific characteristics to the residue in study. Therefore, its objective was to evaluate the biodegradation of the biodiesel washing(purification) water, gotten trough transesterification between soy oil and methanol, by means of production of lipase, using isolated microorganisms from the proper residue. For both, analyses of the initial physicist-chemistries characteristics had been made with the residuary water of the biodiesel washing, then it had been isolated and chosen, by means of determinations of the lipase activity. Following, it was made a test of fat biodegradation, fixing the variables pH (5,95), temperature (35ºC), rotation (180 rpm) and nitrogen concentration (3 g.L-1) and establishing as variable the two microorganism preselected and the time (24, 48, 72, 96 and 120 h). At the time (48 h) and Klebsiella oxytoca microorganism defined, the optimization process of the fat removal in the treatment of the wastewater was initialized. For such, it was used a designed central composite (DCCR), establishing as independent variables pH and nitrogen concentration, the other variable ones had been previously fixed in: temperature 35ºC, rotation 180 rpm and 48 hours. For experimental validation of the model considered for fat removal it was carried through, in triplicate copy, a biodegradation test in the excellent established conditions. These results, on the other hand, had been compared to a kinetics one carried through the same conditions, but using as inoculun the commercial product Hábil FTW SF. The biodiesel purification wastewater had presented high potential of environmental impact, presenting a concentration of O&G of 6,76 g.L-1. From the six isolated microbiological cultures in the decantation tank of this effluent one, two microorganisms (A and B) had been selected presenting one high potential of lipase production, with enzymatic index of 0,56 and 0,57, respectively. Trough DCCR ways it has been concluded that the best point to the maximum efficiency of removal of O&G from the residuary water of biodiesel purification was equivalents to pH 7,5 and 4,00 g.L-1 of nitrogen, resulting in an efficiency of 60% in the removal of fat. The treatment of the wastewater using the proper isolated microorganism from the effluent (Klebsiella oxytoca) was not differentiated from the carried through essays using the commercial product Hábil FTW SF. / O biodiesel é um combustível derivado de biomassa renovável que pode substituir, parcial ou totalmente, o combustível de origem fóssil. O processo de produção de biodiesel é composto das seguintes etapas: preparação da matéria-prima, reação de transesterificação, separação de fases, recuperação e desidratação do álcool, destilação da glicerina e purificação desse combustível renovável, tendo como subproduto a glicerina e como resíduo água de purificação. A água residuária, formada durante a etapa de purificação, apresenta alto teor de óleos e graxas, tendo potencial para contaminar corpos água. Uma das propostas de tratamento deste resíduo é a utilização de hidrólise enzimática por lipases para remoção de óleos e graxas. Devido à especificidade das lipases e sua ampla aplicação tecnológica, verifica-se que é necessário pesquisar novas cepas de micro-organismos produtores desta enzima, com características específicas do resíduo em estudo. Deste modo, teve-se por objetivo neste estudo avaliar a biodegradação da água de lavagem (purificação) do biodiesel, obtido por transesterificação entre óleo de soja e metanol, por meio de produção de lipase, utilizando micro-organismos isolados do próprio resíduo. Para tanto, foram feitas análises das características físico-químicas iniciais da água residuária da lavagem do biodiesel e a partir desse resíduo foram isolados e selecionados micro-organismos com potencial de produção de lipase. Em seguida, foi feito um ensaio de biodegradação de gordura, fixando-se as variáveis: pH (5,95), temperatura (35ºC), rotação (180 rpm) e concentração de nitrogênio (3 g.L-1) e tendo como variáveis os micro-organismos pré-selecionados e o tempo (24, 48, 72, 96 e 120 h). Com o tempo (48h) e o micro-organismo Klebsilla oxytoca, iniciou-se o processo de otimização da remoção de gordura no tratamento da água residuária. Para tal, utilizou-se um Delineamento Composto Central Rotacional (DCCR), tendo como variáveis independentes pH e concentração de nitrogênio; as demais variáveis foram previamente fixadas em: temperatura 35ºC, rotação 180 rpm e tempo 48 h. Para validação experimental do modelo proposto para remoção de gordura foi realizado, em triplicata, um ensaio de biodegradação nas condições ótimas estabelecidas. Estes resultados, por sua vez, foram comparados com uma cinética realizada nas mesmas condições, mas utilizando como inóculo o produto comercial Hábil FTW SF. A água residuária de purificação do biodiesel apresentou alto potencial de impacto ambiental, tendo uma concentração de O&G de 6,76 g.L-1. Das seis culturas microbianas isoladas do tanque decantação deste efluente, dois micro-organismos (A e B) foram selecionados, apresentando um alto potencial de produção de lipase, com índice enzimático de 0,56 e 0,57, respectivamente. Por meio do DCCR, conclui-se que o ponto ótimo para máxima eficiência de remoção de O&G da água residuária de purificação do biodiesel foi equivalente ao pH 7,5 e 4,00 g.L-1 de nitrogênio, obtendo-se uma eficiência de 60% na remoção de gordura. O tratamento da água residuária utilizando o micro-organismo isolado Klebsilla oxytoca, a partir do próprio efluente, não se diferenciou dos ensaios realizados utilizando o produto comercial Hábil FTW SF.

Made available in DSpace on 2017-05-12T14:48:09Z (GMT). No. of bitstreams: 1 Dayane Cristina da Rocha.pdf: 1452913 bytes, checksum: 15c01c66c71278c9a56f1e0eb396f63c (MD5) Previous issue date: 2010-07-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Biodiesel is a derived fuel from renewable biomass that can substitute partially or totally the fossil fuel. The production process of the biodiesel is composed by the following stages: raw material preparation, transesterification reaction, phases separation, alcohol recovery and dehydration, glycerin destillation and purification of the renewable fuel, resulting in glycerin as a by-product and purification wastewater. The formed wastewater during the stage of purification presents high concentration of oils and greases, presenting potential to contaminate bodies of water. One of the treatment proposals of this residue is the enzymatic hydrolysis use by lipases for removal of oils and greases. Due the specificity of lipases and its large technological application, it appears that it is necessary to search new microorganisms producers of this enzyme, with specific characteristics to the residue in study. Therefore, its objective was to evaluate the biodegradation of the biodiesel washing(purification) water, gotten trough transesterification between soy oil and methanol, by means of production of lipase, using isolated microorganisms from the proper residue. For both, analyses of the initial physicist-chemistries characteristics had been made with the residuary water of the biodiesel washing, then it had been isolated and chosen, by means of determinations of the lipase activity. Following, it was made a test of fat biodegradation, fixing the variables pH (5,95), temperature (35ºC), rotation (180 rpm) and nitrogen concentration (3 g.L-1) and establishing as variable the two microorganism preselected and the time (24, 48, 72, 96 and 120 h). At the time (48 h) and Klebsiella oxytoca microorganism defined, the optimization process of the fat removal in the treatment of the wastewater was initialized. For such, it was used a designed central composite (DCCR), establishing as independent variables pH and nitrogen concentration, the other variable ones had been previously fixed in: temperature 35ºC, rotation 180 rpm and 48 hours. For experimental validation of the model considered for fat removal it was carried through, in triplicate copy, a biodegradation test in the excellent established conditions. These results, on the other hand, had been compared to a kinetics one carried through the same conditions, but using as inoculun the commercial product Hábil FTW SF. The biodiesel purification wastewater had presented high potential of environmental impact, presenting a concentration of O&G of 6,76 g.L-1. From the six isolated microbiological cultures in the decantation tank of this effluent one, two microorganisms (A and B) had been selected presenting one high potential of lipase production, with enzymatic index of 0,56 and 0,57, respectively. Trough DCCR ways it has been concluded that the best point to the maximum efficiency of removal of O&G from the residuary water of biodiesel purification was equivalents to pH 7,5 and 4,00 g.L-1 of nitrogen, resulting in an efficiency of 60% in the removal of fat. The treatment of the wastewater using the proper isolated microorganism from the effluent (Klebsiella oxytoca) was not differentiated from the carried through essays using the commercial product Hábil FTW SF. / O biodiesel é um combustível derivado de biomassa renovável que pode substituir, parcial ou totalmente, o combustível de origem fóssil. O processo de produção de biodiesel é composto das seguintes etapas: preparação da matéria-prima, reação de transesterificação, separação de fases, recuperação e desidratação do álcool, destilação da glicerina e purificação desse combustível renovável, tendo como subproduto a glicerina e como resíduo água de purificação. A água residuária, formada durante a etapa de purificação, apresenta alto teor de óleos e graxas, tendo potencial para contaminar corpos água. Uma das propostas de tratamento deste resíduo é a utilização de hidrólise enzimática por lipases para remoção de óleos e graxas. Devido à especificidade das lipases e sua ampla aplicação tecnológica, verifica-se que é necessário pesquisar novas cepas de micro-organismos produtores desta enzima, com características específicas do resíduo em estudo. Deste modo, teve-se por objetivo neste estudo avaliar a biodegradação da água de lavagem (purificação) do biodiesel, obtido por transesterificação entre óleo de soja e metanol, por meio de produção de lipase, utilizando micro-organismos isolados do próprio resíduo. Para tanto, foram feitas análises das características físico-químicas iniciais da água residuária da lavagem do biodiesel e a partir desse resíduo foram isolados e selecionados micro-organismos com potencial de produção de lipase. Em seguida, foi feito um ensaio de biodegradação de gordura, fixando-se as variáveis: pH (5,95), temperatura (35ºC), rotação (180 rpm) e concentração de nitrogênio (3 g.L-1) e tendo como variáveis os micro-organismos pré-selecionados e o tempo (24, 48, 72, 96 e 120 h). Com o tempo (48h) e o micro-organismo Klebsilla oxytoca, iniciou-se o processo de otimização da remoção de gordura no tratamento da água residuária. Para tal, utilizou-se um Delineamento Composto Central Rotacional (DCCR), tendo como variáveis independentes pH e concentração de nitrogênio; as demais variáveis foram previamente fixadas em: temperatura 35ºC, rotação 180 rpm e tempo 48 h. Para validação experimental do modelo proposto para remoção de gordura foi realizado, em triplicata, um ensaio de biodegradação nas condições ótimas estabelecidas. Estes resultados, por sua vez, foram comparados com uma cinética realizada nas mesmas condições, mas utilizando como inóculo o produto comercial Hábil FTW SF. A água residuária de purificação do biodiesel apresentou alto potencial de impacto ambiental, tendo uma concentração de O&G de 6,76 g.L-1. Das seis culturas microbianas isoladas do tanque decantação deste efluente, dois micro-organismos (A e B) foram selecionados, apresentando um alto potencial de produção de lipase, com índice enzimático de 0,56 e 0,57, respectivamente. Por meio do DCCR, conclui-se que o ponto ótimo para máxima eficiência de remoção de O&G da água residuária de purificação do biodiesel foi equivalente ao pH 7,5 e 4,00 g.L-1 de nitrogênio, obtendo-se uma eficiência de 60% na remoção de gordura. O tratamento da água residuária utilizando o micro-organismo isolado Klebsilla oxytoca, a partir do próprio efluente, não se diferenciou dos ensaios realizados utilizando o produto comercial Hábil FTW SF.

Cartilage repair and/or replacement is necessary for many orthopaedic conditions including fissures from blunt trauma, autograft or allograft transplantation, and replacement of focal defects with biological or synthetic constructs. In cartilage repair, initial integration between the host tissue and repair site is desirable to allow for nutrient transport, molecular deposition to enhance fixation, and eventual stress transmission across the interface. It has been postulated that effective transport and crosslinking of newly synthesized collagen molecules across a repair site may be vital to the process of integrative repair, and recent experiments have correlated collagen deposition with the strength of such repair. Other investigations have shown that enzymatic degradation of the cartilage surface may enhance integrative repair and can increase bond strength of an adhesive to cartilage. This study explored a novel approach involving photochemical bonding of cartilage tissue samples through collagen crosslinking as a means to achieve rapid and effective initial fixation, with the goal of enhancing biological integration. Photosensitized collagen gels were first analyzed via FTIR to determine the crosslinking effects with respect to collagen type and photochemical mechanism. Using the photogellation FTIR results as a parametric guide, in vitro mechanical testing of photochemically bonded meniscal fibrocartilage and hyaline articular cartilage tissues was performed using a modified single-lap shear test. Finally, the cellular viability and bond stability of a photochemically bonded cartilage interface was evaluated over seven days of in vitro culture, where the bond strength was assessed by pushout of cores from annular defects. Results of this study have demonstrated the potential of combining enzymatic surface modification with photodynamic techniques to directly bond cartilage tissues for initial fixation.