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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

PEG hydrogels as anti-fouling coatings for reverse osmosis membranes

Sagle, Alyson Conner 16 October 2012 (has links)
Water is becoming increasingly scarce as the demand for fresh water continues to rise. One potential new water resource is purified produced water. Produced water is generated during oil and gas production, and it is often contaminated with emulsified oil, high levels of salt, and particulate matter. Produced water purification using polymer membranes has been investigated, but its implementation is limited by membrane fouling. This study focused on the preparation and application of poly(ethylene glycol) (PEG) hydrogels as fouling-resistant coatings for commercial reverse osmosis (RO) membranes. To prepare fouling-resistant coatings for RO membranes, three series of copolymer hydrogel networks were synthesized using poly(ethylene glycol) diacrylate (PEGDA) as the crosslinker and acrylic acid (AA), 2-hydroxyethyl acrylate (HEA), or poly(ethylene glycol) acrylate (PEGA) as comonomers, and their transport properties were evaluated. The hydrogels have high water uptake and high water permeability, and crosslink density strongly influences water uptake and water permeability. For example, a 100 mol% PEGDA hydrogel contained 61% water by volume, but 80PEGA, which has essentially the same chemical composition but lower crosslink density, contained 72% water by volume. Hydrogel water permeability ranged from 10 to 26 (L [mu]m)/(m² hr bar) and correlates well with water uptake; high water uptake often leads to high water permeability. Additionally, the copolymers have hydrophilic surfaces with a low affinity for oil, based on contact angle measurements using n-decane in water. Commercial RO membranes (AG RO membrane from GE Water and Process Technologies) were coated with PEG hydrogels, and the desalination and fouling resistance properties of the coated membranes were tested. The water flux of coated membranes and a series-resistance model were used to estimate coating thickness; the coatings were approximately 2 [mu]m thick. NaCl rejection for both uncoated and coated membranes was 99.0% or greater. As determined by zeta potential measurements, both uncoated and coated RO membranes are negatively-charged, but coated membranes are less negatively-charged than uncoated RO membranes. Model oil/water emulsions, prepared with either a cationic or an anionic surfactant, were used to probe membrane fouling. In the absence of oil, surfactant charge, and therefore, electrostatic interactions play a significant role in membrane fouling. In the presence of DTAB, a cationic surfactant, the AG RO membrane water flux immediately dropped to 30% of its initial value, but in the presence of SDS, an anionic surfactant, its water flux gradually decreased to 74% of its initial value after 24 hours. However, in both cases, coated membranes exhibited less flux decline than uncoated membranes. Coated membranes also experienced little fouling in the presence of an n-decane/DTAB emulsion. After 24 hours, the water flux of a PEGDA-coated AG RO membrane was 73% of its initial value, while the water flux of an AG RO membrane fell to 26% of its initial value. Conversely, both coated and uncoated membranes fouled significantly in the presence of an n-decane/SDS emulsion, indicating that oil fouling is controlled both by electrostatic and hydrophobic interactions. Overall, this work provides answers to some of the fundamental questions posed regarding the viability of using modified membranes for produced water treatment. / text
72

The development of a polymer microsphere multi-analyte sensor array platform

Goodey, Adrian Paul 13 May 2015 (has links)
The development of a chip-based sensor array composed of individually addressable polystyrene-polyethylene glycol and agarose microspheres has been demonstrated. The microspheres are selectively arranged in micromachined cavities localized on silicon wafers. These cavities are created with an anisotropic etch and serve as miniaturized reaction vessels and analysis chambers. The cavities possess pyramidal pit shapes with trans-wafer openings that allow for both fluid flow through the microreactors/analysis chambers as well optical access to the chemically sensitive microspheres. Identification and quantification of analytes occurs via colorimetric and fluorescence changes to receptor and indicator molecules that are covalently attached to termination sites on the polymeric microspheres. Spectral data is extracted from the array efficiently using a charge-coupled device (CCD) allowing for the near-real-time digital analysis of complex fluids. The power and utility of this new microbead array detection methodology is demonstrated here for the analysis of complex fluids containing a variety of important classes of analytes including acids, bases, metal cations, sugars and antibody reagents. The application of artificial neural network analyses to the microbead array is demonstrated in the context of pH measurements. To assess the utility of the analysis and gain an understanding of the molecular level design of the sensor, parameters such as the choice of the indicator dyes, array size, data pre-processing techniques, as well as different network types and architectures were evaluated. Additionally, the development of miniaturized chromatographic systems localized within individual polymer microspheres and their incorporation into an array is reported. The integrated chromatographic and detection concept is based on the creation of distinct functional layers within the microspheres. Such beads have been incorporated into the array platform and used for speciation and concentration determination of aqueous metal cation solutions. / text
73

Efficacy and side-effect profiles of lactulose, docusate sodium, and sennosides compared to PEG in opioid-induced constipation: A systematic review

Kerridge, Teresa A. Unknown Date
No description available.
74

Lamination of Organic Solar Modules

Kalldin, Sofie January 2014 (has links)
As the Worlds energy demand is increasing we need more of our energy to be generated from resources that affect the climate as little as possible. Solar power could be the solution if there were solar panels with a less energy demanding production than the established silicon based solar modules. Printable organic solar cells will enable a cheap production process, thus they are mainly made out of polymers in solution. However, to be able to decrease the total cost of the solar modules the commonly used indium tin oxide (ITO) for the transparent electrode needs to be replaced by a less expensive material. If the cheap, high conductive and transparent polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) could replace ITO the cost of organic solar modules would significantly decrease. For PEDOT:PSS to be able to replace ITO there are requirements that have to be met. The transparent electrode needs to be apart from transparent, highly conductive, have a low contact resistance to the other materials in the organic solar cell and be printable. In this study it has been shown that the PEDOT:PSS film with Zonyl and Diethylene Glycol (DEG) as an secondary dopant, is capable of laminating to thin films made out of PEDOT:PSS, metal or a polymer fullerene blend. The contact resistances between two PEDOT:PSS films and PEDOT:PSS film and a metal film proved to be low. When laminating to a metal film an interlayer of Silver Nano Wires (AgNW) was needed to achieve a low contact resistance.
75

\"Valor nutricional de espécies arbóreo-arbustivas nativas da caatinga e utilização de tratamentos físico-químicos para redução do teor de taninos\" / Nutritional value of plants from caatinga and the use of physical and chemical treatments to reduce tannin levels

Eduardo Fernando Nozella 21 November 2006 (has links)
As espécies nativas do semi-árido nordestino constituem uma importante fonte de proteína para o rebanho da região, especialmente durante a estação seca. Contudo, a composição química dessas plantas, especialmente teores de fibra, proteína bruta e compostos secundários, apresenta variações ao longo do ano, em função do ciclo fenológico. O conteúdo de taninos nas plantas pode variar de acordo com as condições climáticas e geográficas. Objetivou-se com o presente estudo: (i) avaliar a composição química de plantas de três Estados do nordeste brasileiro; (ii) verificar o efeito dos taninos na produção de gases; (iii) testar métodos de detanificação, para melhorar o valor nutritivo dessas plantas. O estudo foi dividido em três capítulos. No primeiro, foram avaliadas espécies nativas do semi-árido de Pernambuco, Bahia e Ceará por meio de análises químicas e técnica de produção de gases: angico - Anadenanthera macrocarpa, aroeira - Astronian urundeuva, catingueira - Caesalpinia bracteosa, jucazeiro - Caesalpinia ferre, jurema preta - Mimosa hostilis, leucena - Leucaena leucocephala, malva branca - Sida cordifolia, maniçoba - Manihot pseudoglaziovii, pau branco - Auxemma oncocalyx e sabiá - Mimosa caesalpinifolia. No segundo e terceiro capítulos, foram testados métodos de secagem e aplicação de soluções alcalinas (cinzas de madeira e hidróxido de cálcio) e de polietileno glicol para redução dos efeitos dos taninos. Os resultados obtidos pela avaliação da composição química nas três regiões demonstraram que as espécies estudadas representam uma importante reserva de forragem para os ruminantes e que o teor de compostos fenólicos deve ser monitorado, uma vez que algumas dessas espécies apresentam altos teores destes compostos. Os métodos de secagem testados não foram eficientes para minimizar a ação dos taninos e os tratamentos com soluções alcalinas e com PEG foram eficazes para reduzir a concentração dos taninos, quando medida pela análise química. O tratamento com PEG resultou uma resposta na diminuição da atividade dos taninos no bioensaio / The typical vegetation of the semi-arid region of northeast Brazil is considered an important source of protein for the animals, mainly during the dry season. However, the chemical composition of the plants, as fiber, protein and secondary compounds change during the year with the different stage of the plants. The tannin concentration varies according to climatic and geographic conditions. The aims of this study were: (i) to evaluate the chemical composition of plants of three regions in the northeast Brazil; (ii) to verify the effect of tannins on gas production; (iii) to use detanification methods to improve the nutritional value of those plants. The study contains three chapters. In the first chapter, the following species of plants from Pernambuco, Bahia and Ceara were evaluated by chemical analysis and gas production: angico - Anadenanthera macrocarpa, aroeira - Astronian urundeuva, catingueira - Caesalpinia bracteosa, jucazeiro - Caesalpinia ferre, jurema preta - Mimosa hostilis, leucena - Leucaena leucocephala, malva branca - Sida cordifolia, manicoba - Manihot pseudoglaziovii, pau branco - Auxemma oncocalyx and sabia - Mimosa caesalpinifolia. In the second and third chapters various detanification methods were tested, as drying processes and application of alkaline solutions (wood ash and calcium hydroxide) and polyethylene glycol application. The chemical analysis showed that all the plants studied could be used as animal feed, but the phenolics contents could be a detrimental factor and should be monitored. The drying methods were not efficient to minimize tannin effects as showed using the gas production. The treatment with wood ash, calcium hydroxide and polyethylene glycol resulted in a decrease of tannins concentration, but only polyethylene glycol treatment decreased tannins activity during the gas production.
76

Características nutricionais e fatores antinutricionais na fermentação ruminal in vitro de espécies arbóreo-arbustivas nativas e exóticas em área de Caatinga no Sertão de Pernambuco / Nutritional characteristics and antinutricional factors in in vitro rumen fermentation assay of native and exotic arboreal species from savanna area in Pernambuco

Ronaldo Carlos Lucas 29 June 2012 (has links)
A vegetação nativa do sertão nordestino é rica em espécies forrageiras nos estratos herbáceo, arbustivo e arbóreo. Estudos têm revelado que acima de 70% das espécies botânicas da caatinga participam significativamente da composição da dieta dos ruminantes domésticos. Estrategicamente, as espécies lenhosas são fundamentais no contexto de produção e disponibilidade de forragem no semiárido Nordestino. Objetivou-se com este trabalho: (1) Quantificar a composição química bromatológica e os compostos fenólicos de leguminosas nativas; (2) Avaliar as características de degradação ruminal e o efeito biológico de plantas taniníferas baseado na técnica de produção de gás in vitro (bioensaio); (3) Estudar os efeitos de dietas constituídas de forrageiras nativas na síntese de nitrogênio microbiano in vitro com marcador 15N e nos parâmetros de fermentação pela técnica de produção gases. Os resultados quanto à composição química e quantificação dos compostos fenólicos das leguminosas taniníferas catingueira (Caesalpinea bracteosa), aroeira (Astronian urundeuva), leucena (Leucaena leucocephala), jureminha (Desmanthus virgatus) e do capim buffel (Cenchrus ciliaris L.) são apresentados. Estas plantas também foram avaliadas por incubação in vitro, juntamente com feno de alfafa (Medicago sativa) como controle, para avaliar o incremento de gás devido à adição de polietilenoglicol (PEG). As leguminosas apresentaram na produção de gases menor atividade biológica dos taninos com adição do PEG, sendo positivos os coeficientes de correlações entre o incremento na produção de gases na presença do PEG e os parâmetros de produção de metano, demonstrando o potencial destas plantas taniníferas para reduzir a produção de metano ruminal, com destaque para leucena e aroeira, com elevado teor proteic e menores teores de fibras. No capitulo 4 são apresentados os resultados do ensaio in vitro para avaliar os efeitos de dietas constituídas de forrageiras nativas da região de Caatinga do NE Brasileiro na síntese de nitrogênio microbiano, utilizando o marcador 15N; e os parâmetros de fermentação pela técnica in vitro de produção gases. As dietas foram constituídas com as espécies catingueira (Caesalpinea bracteosa), aroeira (Astronian urundeuva), leucena (Leucaena leucocephala), jureminha (Desmanthus virgatus) e capim buffel (Cenchrus ciliaris L.), oriundas de três coletas (Agosto de 2008, Março de 2009 e Agosto de 2009). Dois níveis (50% e 30%) de plantas foram usadas em cada dieta simulando sistema CBL (Caatinga, Capim buffel + Leucena). Em geral, as dietas experimentais apresentaram em sua composição química, elevado teor de proteína bruta baixa concentração de compostos fenólicos. Quando estas dietas foram avaliadas através da técnica de produção de gás in vitro, as dietas mostraram redução na emissão de metano, e os parâmetros fermentativos sugeriram que houve mudanças nas rotas de fermentação das dietas. O uso de leguminosas nativas da caatinga pode ser uma alternativa na região semi-árida, principalmente, oferecendo características favoráveis como: valor nutricional, potencial produtivo e rusticidade. No entanto, a viabilidade, no ponto de vista nutricional pode limitar o uso de algumas espécies, devido à alta concentração de compostos fenólicos, principalmente os taninos condensados. / The native vegetation of Northeastern region of Brazil is rich in forage species in the herbaceous, shrubby and arboreal strata. Studies have revealed that over 70% of botanical species from the caatinga participate significantly in the composition of the diet of domestic ruminants. Strategically, the woody species are fundamental in the context of production and availability of forage in such semi-arid area. The objectives of this work were: (1) to quantify the chemical composition and the phenolic compounds of native legumes form the semi-arid region of Pernambuco; (2) to assess the rumen degradation characteristics and biological effect of such tanninferous plants based on in vitro gas production technique (bioassay); (3) to study the effects of diets consist of the native forage on microbial nitrogen synthesis in vitro using 15N as marker and the parameters of fermentation by gas production technique. Chapter 4 presented the results of the in vitro test to assess the effects of diets consist of native forage of Caatinga region of Brazilian NE upon the synthesis of microbial nitrogen using the 15N as tracer, and fermentation parameters. Diets were formed by the species catingueira (Caesalpinea bracteosa), aroeira (Astronian urundeuva), leucena (Leucaena leucocephala), jureminha (Desmanthus virgatus) e capim buffel (Cenchrus ciliaris L.), from three collections (August 2008, March 2009- August 2009). Two levels (50 and 30%) of the plants were used in each diet simulating CBL system (Caatinga + Buffel Grass + Leucena). In general, the experimental diets presented in their chemical composition high crude protein content and low concentration of phenolic compounds. When these diets were evaluated by the in vitro gas production technique, diets showed reduction of methane emission, and the fermentative parameters suggested that there have been changes of fermentation routes of diets. The use of legumes native to caatinga may be an alternative in the semi-arid region, primarily by offering favorable characteristics as: nutritional value, productive potential and homeliness. However, the viability, in nutritional point of view the use of some species can be limiting, because of high concentration of phenolic compounds in particular the condensed tannins.
77

Síntese e caracterização de derivados de hemoglobina para aplicação terapêutica / Synthesis and characterization of hemoglobin based oxygen carriers for therapeutic application

Marcos Camargo Knirsch 09 September 2015 (has links)
A transfusão de sangue é uma intervenção terapêutica capaz de salvar muitas vidas. Entretanto, transfusões também apresentam uma alta gama de possíveis eventos adversos, questões logísticas, econômicas e sociais. Dentre as principais preocupações terapêuticas estão a incompatibilidade (principalmente do sistema ABO), a transmissão de microrganismos patogênicos, os distúrbios imunomodulatórios, as reações hemolíticas, o aumento estatístico do risco de morte proporcional ao volume de sangue infundido, dentre outros. Diversas alternativas às transfusões sanguíneas são propostas na literatura científica, dentre elas o desenvolvimento de transportadores de oxigênio que utilizam a hemoglobina, comumente intitulados substitutos sanguíneos. Neste âmbito, o presente estudo teve como objetivo o desenvolvimento de uma rota de síntese e a síntese de partículas de gelatina contendo hemoglobina polimerizada. Para tanto, realizou-se a síntese do polietileno glicol bis-[succinimidil succinato], extraiu-se e polimerizou-se com glutaraldeído ou polietileno glicol bis-[succinimidil succinato] hemoglobina de sangue bovino e, partículas de gelatina coriácea ou óssea contendo hemoglobina polimerizada foram sintetizadas e caracterizadas. A síntese do polietileno glicol bis-[succinimidil succinato] (SSPEG) foi caracterizada por espectroscopia RAMAN, análise diferencial de calorimetria (DSC) e os resultados obtidos indicaram o sucesso das reações. O produto da reação de polimerização da hemoglobina e albumina com o SSPEG foi verificado por SDS-PAGE e os resultados obtidos indicaram a formação com sucesso de polímeros de alta massa molecular. As partículas contendo hemoglobina polimerizada geradas com gelatina coriácea apresentaram diâmetro hidrodinâmico de 1370 nm, dispersividade de 0,029 e potencial zeta de -36,1 mV. As partículas contendo hemoglobina polimerizada geradas com gelatina óssea apresentaram diâmetro hidrodinâmico de 438 nm, dispersividade de 0,563 e potencial zeta de -24,5 mV. Os resultados obtidos sugerem a aplicabilidade da gelatina coriácea para a produção de partículas contendo hemoglobina polimerizada com possível aplicação como transportador de oxigênio. / Blood transfusion is a therapeutic intervention that can save many lives. However, transfusion is also related to several possible adverse therapeutic events and logistic, economic and social concerns. Among the major therapeutic concerns are incompatibility (mainly of the ABO group system), pathogenic microorganisms\' transmission, immunomodulatory disturbances, hemolytic reactions, death risk increase that is proportional to the infused volume, among others. Several alternatives to blood transfusion are proposed in the scientific literature. Among them is the development of hemoglobin based oxygen carriers, commonly entitle blood substitutes. To this extent, the present work aimed to develop a synthetic route and to synthesize gelatin particles containing polymerized hemoglobin. To this purpose PEG bis(succinimidyl succinate) was synthesized, bovine hemoglobin was extracted and polymerized with glutaraldehyde or PEG and polyhemoglobin contained particles of gelatin from leather or bones were synthesized and characterized. PEG bis(succinimidyl succinate) synthesis was characterized by RAMAN spectroscopy and by differential scanning calorimetry (DSC) and the obtained results indicated the successful synthesis. The reaction product of the polymerization of hemoglobin or albumin with PEG was verified by SDS-PAGE and the results indicated the successful formation of high molecular mass polymers. The particles generated with leather gelatin and polyhemoglobin had a hydrodynamic diameter of 1370 nm, dispersity of 0.029 and zeta potential of -36.1 mV. Particles generated with bone gelatin and polyhemoglobin had hydrodynamic diameter of 438 nm, dispersity of 0.563 and zeta potential of -24.5 mV. The obtained results suggest the applicability of leather gelatin for the production of polyhemoglobin containing particles aiming to the development of a hemoglobin based oxygen carrier.
78

Obtenção de micropartículas contendo dispersões sólidas de praziquantel por spray congealing / Obtain microparticles containing solid dispersions of praziquantel by spray congealing

Marcela Olaia Machado 18 April 2011 (has links)
MACHADO, M. O. Obtenção de micropartículas contendo dispersões sólidas de praziquantel por spray congealing. 2011. 120f. Dissertação (Mestrado). Faculdade de Ciências Farmacêuticas de Ribeirão Preto - Universidade de São Paulo, Ribeirão Preto, 2011. A esquistossomose é uma verminose provocada pelo Schistosoma mansoni. Sua prevalência no Brasil é de aproximadamente 10 milhões de pessoas infectadas. O tratamento é feito com o praziquantel, um fármaco anti-helmíntico para uso tanto humano como veterinário. Está classificado no sistema de classificação biofarmacêutico como de classe II, dos fármacos que possuem baixa solubilidade e alta permeabilidade necessitando de um estudo para melhorar a sua solubilidade e consequentemente sua taxa de dissolução. Para isso, técnica escolhida nesse estudo foi a de obtenção de dispersões sólidas de praziquantel, microparticuladas, por spray congealing. Esta técnica prepara micropartículas atomizando-se a solução do fármaco em um carreador fundido, dispensando solventes orgânicos ou aquosos. Foram preparadas dispersões sólidas e misturas físicas com formulações de polietilenoglicol 6000:praziquantel nas proporções de 10, 15 e 20% de praziquantel e polietilenoglicol 6000:sorbitol:praziquantel nas proporções de 10, 15, 20 e 40% de praziquantel e determinou-se a sua solubilidade em todas as amostras. As dispersões sólidas preparadas obtiveram um aumento significativo na solubilidade do fármaco em relação ao praziquantel puro e as formulações com polietilenoglicol 6000 e sorbitol apresentaram uma melhoria significante de solubilidade em relação às que continham apenas polietilenoglicol, com p<0,05. Porém ao realizar a atomização no spray a formulação adquiriu características adesivas impossibilitando o sucesso da utilização da técnica de spray congealing. Com isso escolheu-se a formulação de polietilenoglicol 6000:praziquantel nas concentrações de 10, 15 e 20% de praziquantel e realizou-se um planejamento fatorial do tipo Box-Behnken, num total de 15 experimentos, estudando a vazão de atomização, a vazão de dispersão e a porcentagem de praziquantel. Para todas as amostras realizou-se as análises por calorimetria exploratória diferencial, termogravimetria, infravermelho e difração de raios-X. Estas análises mostraram que provavelmente não houve interações fármaco/polímero. Na análise das propriedades de escoabilidade as micropartículas apresentaram fluxo de excelente a tolerável. Estas tiveram um aumento da solubilidade do fármaco que variou de 62,6 a 79% em relação ao praziquantel puro. O diâmetro médio das partículas ficou entre 145 a 215µm. As micropartículas tiveram um aumento da taxa de dissolução de 3,18 vezes em comparação ao praziquantel puro, 2,3 vezes em relação mistura física de 10% e 2,14 vezes em relação à dispersão sólida de 10%. A análise morfológica mostrou partículas irregulares e com superfície rugosa apresentando pequenos cristais do fármaco. A técnica apresentou uma excelente eficiência de encapsulação que variou de 88 a 108%. Pela análise de variância dos dados tivemos que para a solubilidade quanto menor a porcentagem de praziquantel na amostra, maior o aumento da solubilidade e para o tamanho de partícula, quanto maior a vazão de dispersão, maior é a partícula. Com esses resultados pode-se concluir que a técnica de spray congealing apresentou resultados satisfatórios, sendo uma técnica eficiente, rápida e muito promissora para a preparação de dispersões sólidas. / Schistosomiasis is a parasitic disease caused by the worm Schistosoma mansoni. Its prevalence in Brazil is around 10 million infected people. Treatment is done with praziquantel, an antihelmintic drug both for human and animal use. As it is a class II drug of low solubility and high permeability according to the Biopharmaceutics Classification System (BCS), it is highly valuable to perform a study to improve the solubility and dissolution rates of praziquantel. That is the aim of the present work. Spray congealing was the technique used to obtain solid dispersions of praziquantel. It consists of atomizing the solution or suspension containing the drug in a melting carrier without the need of organic or aqueous solvents. Solid dispersions and physical mixtures were prepared using polyethylene glycol 6000:praziquantel in proportions 10%, 15%, and 20% of praziquantel, and using polyethylene glycol 6000:sorbitol:praziquantel in proportions 10%, 15%, 20%, and 40% of praziquantel. Solubility tests were performed in each sample. Solid dispersions had a significant increase in solubility rate compared to pure praziquantel. The formulations containing polyethylene glycol 6000 and sorbitol had a significant improvement in solubility rate compared to the ones with polyethylene glycol only (p<0,05). However, during the atomization through spray congealing technique, the formulation acquired sticky characteristics, impairing the success of such technique. Thus, the formulation of polyethylene glycol 6000:praziquantel in concentrations 10%, 15% and 20% of praziquantel was chosen and a factorial design type Box-Behnken was planned, in a total of 15 experiments, to study the parameters: flow of the atomization, flow rate of the dispersion, and the percentage of praziquantel. It was carried out an analysis of the samples of physical mixtures, microparticles, and solid dispersions in each proportion through differential exploratory calorimetry, thermogravimetry, infrared ray and X-ray diffraction. The analysis showed that probably there were no interactions between the drug and the polymer. Flow rate analysis of microparticles presented a level from excellent to tolerable, showing an increase in solubility that ranged from 62.6% to 79% compared to pure praziquantel. The average diameter of the particles ranged from 145 to 215m, which is a reasonable size to improve solubility and properties of the flow. Microparticles had an increase in dissolution rate of 3.18 times compared to pure praziquantel, 2.3 times in relation to physical mixture of 10%, and 2.14 times in relation to solid dispersion of 10%. Morphological analysis revealed irregular particles with wrinkled surface with small crystals of the drug. Photomicrographs showed that there was agglomeration during spray congealing. The technique exhibited an excellent efficacy of encapsulation that ranged from 88% to 108%. Variance analysis for the studied factors showed that only solubility and particle size exhibited values with significant statistical difference. For solubility, the lower the percentage of praziquantel in the sample, the higher the increase in solubility. For particle size, the higher the flow of dispersion, the bigger the particle. From the study carried out, it can be concluded that spray congealing is an efficient, quick and promising technique for preparation of solid dispersions.
79

Grandezas excesso de soluções líquidas binárias de glicóis + água a diferentes temperaturas e pressão atmosférica / Excess properties of binary liquid mixtures of glycols + water at different temperatures and atmospheric pressure

Hoga, Heloisa Emi 26 August 2018 (has links)
Orientadores: Pedro Luiz Onófrio Volpe, Ricardo Belchior Tôrres / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-26T22:29:35Z (GMT). No. of bitstreams: 1 Hoga_HeloisaEmi_D.pdf: 3636468 bytes, checksum: 5e4d8bd5f23dc45b0e386f59f4dd3f74 (MD5) Previous issue date: 2015 / Resumo: Propriedades excesso têm sido um caminho qualitativo e quantitativo para predizer o desvio da idealidade de soluções líquidas binárias. Além disso, as grandezas excesso têm sido usadas para desenvolver modelos e novas teorias de soluções. Neste trabalho teve como objetivo o estudo experimental de grandezas volumétricas, viscosimétricas, acústicas e das entalpias excesso de soluções líquidas binárias de água + etanol, ou + etileno glicol, ou + dietileno glicol, ou + trietileno glicol, ou + polietileno glicol 200 (PEG 200), ou + polietileno glicol 300 (PEG 300), ou + polietileno glicol 400 (PEG 400), ou + polietileno glicol 600 (PEG 600), ou + glicerol em função da composição, a diferentes temperaturas e à pressão atmosférica. Os dados de densidade e de velocidade do som foram determinados usando um densímetro e velocímetro (Anton Paar, Modelo DSA 5000). Os valores de viscosidade foram determinados usando um viscosímetro (Anton Paar, Modelo SVM 3000). Os valores da entalpia foram determinados utilizando um microcalorímetro (Thermal Activity Monitor, Titration mode, LKB2277, Thermometric). As temperaturas estudadas foram de 293,15, 298.15, 303,15 e 308,15 K. Somente a entalpia foi estudada a 298,15 K. Os resultados experimentais foram usados para calcular o volume molar excesso, o desvio da compressibilidade isentrópica, o desvio da viscosidade, a energia de Gibbs de ativação excesso e a entalpia molar excesso. As propriedades excesso foram correlacionadas usando os polinômios do tipo Redlich-Kister e Myers-Scott. Os resultados foram comparados e discutidos com base nas interações intermoleculares entre os componentes estudados / Abstract: Excess properties have been a qualitative and quantitative way to predict ideality deviation of liquid binary mixtures. Moreover the excess properties have been used to development molecular theories and new solution models. In this study, density, speed of sound, viscosity and enthalpy of binary mixtures of water + ethanol, or + ethylene glycol, or + diethylene glycol, or + triethylene glycol, or + polyethylene glycol 200, or + polyethylene glycol 300, or + polyethylene glycol 400, or + polyethylene glycol 600, or + glycerol have been determined as a function of composition at several temperatures and atmospheric pressure. The density and speed of sound data were determined using a density and sound velocity meter (Anton Paar, Model DSA 5000) The viscosity data was determined using a viscometer (Anton Paar, Model SVM 3000). The enthalpy date was determined using a microcalorimeter (Thermal Activity Monitor, Titration mode, LKB2277, Thermometric). The temperatures studied were 293.15, 298.15, 303.15 and 308.15 K. Only enthalpy data was measured at 298.15 K. The experimental results have been used to calculated the excess molar, deviations in isentropic compressibility, deviations in viscosity, excess Gibbs free energy of activation of viscous flow and excess molar enthalpy. The excess properties were correlated by using a Redlich-Kister and Myers-Scott polynomial equation. The results were discussed on the basis of intermolecular interactions between the components of the analyzed mixtures / Doutorado / Físico-Química / Doutora em Ciências
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Resposta imune induzida em camundongos por imunização transcutânea com proteína recombinante LipL32 de leptospira. / Immune response induced in mice by transcutaneous immunization with recombinant protein LipL32 of leptospira.

Pamela Siumey Liu 28 January 2016 (has links)
A imunização transcutânea (TCI) é uma via atrativa para o desenvolvimento de vacinação livre de agulhas, atuando nas APCs da pele, podendo substituir algumas das imunizações convencionais, em termos de facilidade, segurança e eficácia. O presente estudo avaliou a resposta imune da TCI com proteína recombinante de leptospira LipL32, uma proteína altamente conservada em cepas patogênicas e potente candidata vacinal. A TCI com a LipL32 na região abdominal de C57BL-6 foi capaz de primar o sistema imune, suscitando resposta sistêmica com altos níveis de anticorpos contra o antígeno, após reforços subimunizantes, ID e Tc. O padrão de citocinas em cultivo de células do sangue total dos grupos imunizados indicou que a imunização Tc foi capaz de primar o sistema imune, tanto inato quanto adaptativo. O tratamento local ou a coadministração com surfactantes ou PEG não evidenciou ação emoliente ou adjuvante. A coadministração Tc da LipL32 com MPL-A levou a efeito moderador da reação pro-inflamatória, redirecionando a resposta adaptativa, tanto humoral quanto celular. / Transcutaneous immunization (TCI) offers an attractive pathway for the development of needle-free vaccination by acting on APCs of the skin, showing potential to replace conventional immunization, in terms of safety and efficacy. In this study we evaluated the immune response by TCI with recombinant protein of leptospira LipL32, a highly conserved protein among pathogenic strains, a potential vaccine candidate. TCI with LipL32 was evaluated in C57BL-6 mice abdominal region and was able to confer systemic response with high levels of antibodies after subimmunizing ID and Tc boosters. The pattern of cytokines in cell cultures from whole blood of immunized groups indicated that the TCI was able to prime the immune system, for both innate and adaptive response. Local treatment of the skin or coadministration with surfactants and PEG did not show an emollient and an adjuvant action. Co-administration of LipL32 with MPL-A influenced the antibody response as well as showed a moderating effect of the pro-inflammatory reaction, redirecting the adaptive response.

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