Thin film coatings of ZnO, TiO2, CeOX and BiOX have been deposited on soda lime silica glass through spray pyrolysis. The effects on the optical properties of the coated glass, as well as the possible impacts on the life expectancy and energy efficiency of PV-modules have been studied. ZnO and TiO2 coatings both reduced the transmission of UV radiation of wavelengths destructive to PV-modules. Therefore, both have the potential to increase the life expectancy of PV-modules if used on cover glass. The ZnO thin film also showed an increase in photoluminescence at 377 nm when radiated with UV radiation of 325 nm while TiO2 reduced the photoluminescence. ZnO coatings on the cover glass have the potential to increase the efficiency of PV-modules in addition to UV protection. No CeOX or BiOX films were found to be deposited with the method used. The ZnO and TiO2 coated samples showed a decrease in transmission of light, due to increased reflection and possibly scattering. This needs to be addressed if these kinds of coatings are going to be beneficial for Si PV-modules.

This master thesis deals with the application of various types of surface treatments on selected tropical wood species and the subsequent change of colour due to the effect of natural and simulated UV radiation. Measurements were performed on the following three species: zebrano (Microberlinia brazzavillensis), panga panga (Millettia Stuhlmannii) and african padouk (Pterocarpus soyauxii). As surface treatment were used water-based, polyurethane, oil and solvent-based paint. Samples were exposed to simulated UV radiation. The total duration of radiation was 168 hours. After that the colour changes delta E* were measured by using a spectrophotometer. The aim was to compare the different paints used on all woods and their colour change. The thesis also includes research of light permanency of coating exposed to natural UV radiation.

Plant optical signals can serve as important source of information about biochemical and physiological processes in plants. These signals are influenced by compounds synthesized by plants during primary or secondary metabolism and thus, can also serve as their qualitative and quantitative indicators. Light reaching plant surface (leaf or fruit) can undergo three main pathways- it can be (i) reflected, (ii) absorbed or it can (iii) transmit through plant material. The probability of these three processes depends on particular wavelength of incident irradiation and on the morphological characteristics of plant tissues themselves. As such, plant contains various spectrum of photosynthetic pigments and fluorescent compounds which can either reflect, absorb or pass incident irradiation through at specific wavelengths. Biophysical techniques working with these optical properties of plant pigments and/or other compounds have become universal and common tool in basic and applied research. To quote some example, chlorophyll fluorescence imaging, UV induced fluorescence or spectroscopic techniques are on the top of interest thanks to its non-invasive nature, allowing maintain the integrity of measured cells or the whole plant constituents. The main aim of this thesis is to provide a comprehensive study on the possibility of non-invasive monitoring of phenolic compounds in the leaves and fruits.

Over fifty structurally diverse, novel fluorinated heteroarenes, have been successfully synthesised by SNAr reaction of a range of fluorinated arenes including pentafluoropyridine, hexafluorobenzene, and methyl pentafluorobenzoate by introduction of a range of groups such as imidazole, triazole, benzimidazole, benzotriazole, and carbazole. Different water solubilising side chains were introduced to some of the successfully synthesised fluorinated heteroarenes to improve water solubility and potential biological activity. X-ray crystal structures of over 10 compounds were obtained including those of two macrocyclic compounds containing 21- and 24-membered rings. The synthesised compounds have been characterized by elemental analysis, IR, 1H and 19F spectroscopy and high resolution mass spectrometry. These compounds have been screened for their biological activities and possible interaction with DNA by methods including UV-visible spectroscopy, fluorescence spectroscopy, co-crystallization for X-ray diffraction analysis, and antimicrobial activity. A number of the fluoroaryl benzimidazole derivatives have been tested against K-562 and MCF-7 cell lines and G361 and HOS cell lines. From the all tested compounds three tethered fluoroaryl benzimidazole derivatives demonstrated micromolar inhibition against K-562 and MCF-7 cell lines. These compounds, in addition to 1-tetrafluoropyrid-4-yl-2-tetrafluoropyrid-4-ylsulfanyl-1H-benzimidazole, also demonstrated micromolar inhibition against G361 and HOS cell lines. Two of the compounds were found to activate caspases leading to apoptosis.

Alogliptina (ALG) é um hipoglicemiante oral, que inibe a enzima dipeptidil peptidase – 4 (DPP-4) com alta seletividade e aumenta a secreção de insulina prevenindo a hiperglicemia prandial. Como ALG não está descrita nas farmacopeias, este trabalho objetivou caracterizar a matéria-prima (Capítulo I), desenvolver métodos analíticos (Capítulo II) e avaliar sua estabilidade (Capítulo III), auxiliando no controle de qualidade. No capítulo I, a ALG foi caracterizada através de calorimetria exploratória diferencial (DSC), termogravimetria (TGA) e microscopia eletrônica de varredura (SEM) acoplada a espectrômetro de raios X por dispersão de energia (EDS). A compatibilidade entre a ALG e os excipientes presentes nos comprimidos foi avaliada por DSC, TGA, infravermelho com transformada de Fourier (FTIR), difração de raios-X de pó (XRPD) e microscopia com estágio de aquecimento. ALG apresentou pureza próxima a 99%, com faixa de fusão entre 179,4 e 187,2 °C (pico em 183,3 °C), seguida por decomposição que iniciou em 198,0 °C. Na SEM/EDS, os cristais de ALG mostraram-se predominantemente irregulares e foram detectados traços de impurezas (chumbo e cobre). Alterações na temperatura de fusão da ALG com manitol, estearato de magnésio e nos comprimidos comerciais foram observadas. A microscopia com aquecimento demonstrou que a interação entre manitol e ALG e nos comprimidos é devida à solubilização do fármaco no excipiente fundido, enquanto que na mistura com o estearato de magnésio é devida à fusão do excipiente e do fármaco que ocorrem separadamente, onde o excipiente funde antes que o fármaco. FTIR e XRPD das misturas não detectaram incompatibilidades, somente o aparecimento de bandas adicionais relacionadas aos excipientes. ALG foi compatível com todos os excipientes testados. Estes resultados são importantes para caracterizar, conhecer a estabilidade e a compatibilidade do fármaco. No capítulo II, foram desenvolvidos e validados métodos de cromatografia líquida (LC) indicativos de estabilidade utilizando dois detectores, ultravioleta (UV) e detector de aerossol carregado (CAD) para análise de ALG em comprimidos. Foi utilizada uma coluna C8 (250 mm x 4,6 mm, 5 μm) em modo isocrático, fluxo de 0,8 mL min-1, utilizando acetonitrila e tampão acetato de amônio 10 mM pH 3,5 ajustado com ácido acético (90:10, v/v) como fase móvel e detecção no UV em 275 nm. Os métodos foram lineares no intervalo de 25 - 200 μg mL-1 em ambos os detectores. Os limites de detecção foram de 2,65 e 6,25 μg mL-1 e os de quantificação de 8,84 e 20,85 μg mL-1, respectivamente, para UV e CAD. Os métodos foram precisos e exatos, com desvio padrão relativo menor que 3% e percentuais de recuperação próximos a 100%. Nenhum dos excipientes, ou produtos de degradação interferiu na detecção do fármaco durante os estudos de especificidade. No ensaio de robustez, pequenas alterações no fluxo de fase móvel, pH e concentração de solvente orgânico não afetou significativamente os resultados. O doseamento dos comprimidos obtido com ambos detectores não mostrou diferenças entre si. Os métodos podem ser considerados intercambiáveis e podem ser aplicados como ferramentas para o controle de qualidade de rotina de comprimidos de ALG. No capítulo III foi avaliada a estabilidade térmica da ALG utilizando TGA isotérmica e não isotérmica, e degradação em estufa, analisando as amostras por LC-UV. Na TGA isotérmica a ALG foi submetida a 150, 155, 160, 165, 170 °C, até perda de massa de 10% e os dados foram analisados pelo método de Arrhenius. Na TGA não isotérmica variaram-se as razões de aquecimento, utilizando 2,5, 5,0, 10,0 e 15,0 °C/min até 500 °C. Os dados foram analisados pelo método de Ozawa e de Kissinger. Na degradação em estufa o fármaco foi submetido as temperaturas de 130, 140, 150, 155, 160 e 170 °C. Os parâmetros cinéticos foram obtidos por Arrhenius. ALG segue degradação de zero ordem, onde a velocidade de degradação independe da concentração do reagente. A perda de massa está relacionada à perda química. Os parâmetros cinéticos variaram de acordo com o modelo matemático aplicado. A energia de ativação variou de 26 a 45 kcal/mol. O fármaco degradado demonstrou ser menos tóxico em ensaio de citotoxicidade em células CRIB do que o fármaco não degradado. Os métodos desenvolvidos e a caracterização realizada mostram-se úteis para o adequado controle de qualidade do fármaco. / Alogliptin (ALG) is an oral hypoglycemic agent, which inhibits the enzyme dipeptidyl peptidase - 4 (DPP-4) with high selectivity and increase insulin secretion, preventing postprandial hyperglycemia. ALG is not described in any pharmacopeia. In this context, this study aimed to characterize the active pharmaceutical ingredient (Chapter I), to developed assay methods (Chapter II) and to evaluate the stability (Chapter III), assuring the adequate quality control. In Chapter I, ALG was characterized by differential scanning calorimetry (DSC), thermogravimetry (TGA) and scanning electron microscopy (SEM) coupled with energy dispersive spectrometer X-ray (EDS). The compatibility between ALG and the excipients present in the commercial tablets was evaluated by DSC, TGA, Fourier transform infrared (FTIR), X-ray powder diffraction (XRPD) and hot stage microscopy. ALG presented purity close to 99%, with a melting range between 179.4 to 187.2 °C (peak at 183.33 °C), followed by decomposition which began at 198 °C. In the SEM/EDS the crystals of ALG were predominantly irregulars and it were detected traces of impurities (lead and copper). Alterations in melting temperature of ALG with mannitol, magnesium stearate and in tablets were observed. The hot stage microscopy showed that the interactions between mannitol and ALG and in the tablets were due to the solubilization of the drug in the fused excipient, and in the mixture with magnesium stearate, it was due to the melting of the drug and excipient separately, where the excipient started the melting prior of the drug. FTIR and XRPD of the mixtures did not detect incompatibilities, only the appearance of additional bands related to the excipients. ALG was compatible with all excipients tested. These results are important to characterize, to know the drug stability and compatibility. In Chapter II, liquid chromatography (LC) methods indicative of stability were developed and validated using two detectors, ultraviolet (UV) and charged aerosol detector (CAD) for ALG tablets. It was used a C8 column (250 mm x 4.6 mm, 5 um) in isocratic mode, flow rate of 0.8 ml min-1 using acetonitrile and ammonium acetate buffer 10 mM, pH 3.5 adjusted with acid acetic acid (90:10, v/v) as mobile phase and UV detection at 275 nm. The methods were linear in the range of 25 - 200 μg ml-1 in both detectors. Limits of detection were 2.65 and 6.25 μg mL-1, and of quantification were 8.84 and 20.85 μg mL-1, respectively, for UV and CAD. The methods were accurate and precise, with a relative standard deviation lower than 3% and recovery close to 100%. None of the excipients or degradation products showed interference in the drug detection during specificity studies. In the robustness test, small changes in the mobile phase flow, pH and organic solvent concentration did not significantly affect the results. The results for tablets obtained with both detectors showed no differences. The methods may be considered interchangeable, and they can be used as tools for routine quality control of ALG tablets. In Chapter III the thermal stability of the ALG was evaluated using isothermal and non-isothermal TGA, as well as oven, and samples were analyzed by LC-UV. In the isothermal TGA the ALG was subjected to 150, 155, 160, 165, 170 °C until a mass loss of 10% and the data were analyzed by the Arrhenius method. In non-isothermal TGA the heating rates were varied using 2.5, 5.0, 10.0 and 15.0 °C/min until 500 °C. Data were analyzed by the Ozawa and Kissinger method. In oven the drug was subjected to 130, 140, 150, 155, 160, and 170 °C. The kinetic parameters were obtained by Arrhenius. ALG follows zero-order degradation, where the rate of degradation is independent of the concentration of any reagent. Mass loss is related to chemical reactions. The kinetic parameters varied according to the applied mathematical model. The activation energy ranged from 26 to 45 kcal / mol. The degraded drug was shown to be less toxic in cytotoxicity assay using CRIB cells than the non-degraded drug. The methods developed and the characterization performed proved to be useful for adequate quality control tests of the drug.

No description available.

Phylogeny, phylogeography and evolution of UV reflecting patterns were studied in 12 species of the genus Gonepteryx. Sequences of one mitochondrial (COI) and one nuclear gene (Wingless) were used for phylogenetic analyses and reconstruction of the biogeographical events. The results were later compared with the extent of UV reflecting pattern to construct the ancestral situation and evolution of the UV pattern within the genus.

Made available in DSpace on 2014-06-11T19:25:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-12-18Bitstream added on 2014-06-13T19:12:22Z : No. of bitstreams: 1 maceti_h_me_rcla.pdf: 484546 bytes, checksum: 6d093c2c96c1a1dba6ae5a651183c6b5 (MD5) / Sonogéis de sílica foram preparados a partir da sonohidrólise de tetraetilortosilicato (TEOS) e, após o envelhecimento, a fase líquida do gel foi trocada por acetona, durante a fase saturada do processo. A evolução estrutural durante a secagem do sonogel úmido com a fase líquida trocada por acetona foi estudada por espalhamento de raio-x a baixo ângulo (SAXS). A evolução estrutural do xerogel derivado do sonogel com fase líquida trocada por acetona, foi estudada em função da temperatura, por meio de espectroscopia de absorção UV-visível, medidas de densidade real e aparente, medidas de contração linear, e análises térmicas (DTA, TG e DL). Os períodos associados à evolução estrutural determinados por SAXS estão de acordo com os períodos clássicos determinados a partir das características da taxa de evaporação da fase líquida, na obtenção de xerogéis. O gel úmido pode ser descrito como formado por partículas primárias (microclusters), com densidade de cerca de 1,8 g/cm3, tamanho característico a ~ 0,67 nm e superfície fractal, que se juntam para formar uma estrutura fractal de massa, com dimensão fractal de massa D ~ 2,2 e comprimento característico ? ~ 6,7 nm. À medida que a rede colapsa durante o período de taxa de evaporação constante, no qual o gel se mantém saturado com a frente de evaporação na superfície externa do gel, a estrutura fractal de massa vai se compactando, aumentando D e diminuindo ?, com alisamento da superfície fractal dos microclusters. O xerogel obtido ao término do processo de secagem apresenta características de um sistema com poros vazios e partículas não fractais, com superfície de interface lisa e área de superfície de cerca de 385 m2/g. Os resultados das medidas de densidade aparente, de DTA e TG, mostram que os géis perdem resíduos... . / Silica sonogels were prepared from the sonohydrolysis of tetraetilortosilicate (TEOS) and the liquid phase of the gel was exchanged by acetone during the saturated stage of the process. The structural evolution of the drying of the wet exchanged sonogel was studied by small-angle x-ray scattering (SAXS). The structural evolution of the xerogel derived from the exchanged sonogel was studied as a function of the temperature by means of UV-visible absorption spectroscopy, bulk and skeletal density measurements, linear contraction measurements, and thermal analysis (DTA, TG and DL). The periods associated to the structural evolution as determined by SAXS are in agreement with those classical ones as determined from the features of the evaporation rate of the liquid phase in the obtaining of xerogels. The wet gel can be described as formed by primary particles (or microclusters) with density of about 1.8 g/cm3, characteristic length a ~ 0.76 nm e surface fractal, linking together to form mass fractal structures with mass fractal dimension D ~ 2.2 in a length scale ? ~ 6.7 nm. As the network collapses, while the liquid/vapor meniscus is kept at the external evaporation surface of the gel, the mass fractal structure becomes more compacted by increasing D and decreasing ?, with smoothing of the fractal surface of the microclusters. The xerogel obtained at the end of the drying process presents characteristics of a system with empty pores and non-fractal particles, with smooth interface surface and surface area of about 385 m2/g. The results of bulk density measurements and of DTA and TG thermal analysis show that the gels lose organic residuals and more strongly bonded water at temperatures up to 200-250 oC. This event is related with the increase of the absorption in the UV region, which was found at temperatures up... (Complete abstract, click electronic address below).

Made available in DSpace on 2014-06-11T19:27:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-04-26Bitstream added on 2014-06-13T18:56:11Z : No. of bitstreams: 1 campos_a_me_rcla.pdf: 4152569 bytes, checksum: 41a529d2c0be5a0a79eb44e0ec1448ea (MD5) / Os plasticos constituem um dos materiais mais utilizados em nosso cotidiano. Assim, os residuos plasticos tem aumentado bastante e hoje representam 20% do total do volume de residuos, em lixoes municipais. O PVC (policloreto de vinila) e um polimero sintetico, instavel em relacao ao calor e luz, que degrada a temperatura relativamente baixa (aproximadamente 130oC), e libera HCl. A desidrocloracao gera novas especies na cadeia polimerica, ou seja, sequencias de polienos que podem ser verificadas atraves da espectroscopia de absorcao na faixa do UV-Visivel. A reciclagem do PVC apresenta algumas dificuldades intrinsecas ao comportamento do polimero, durante o processo tecnologico e, alem disso, sua biodegradacao e dificil. O PCL (poli α-caprolactona), um poliester sintetico, e sensivel a acao de enzimas microbianas, e pode sofrer hidrolise e degradacao. A mistura desses polimeros, isto e, a blenda de PVC e PCL pode constituir um meio para facilitar o ataque microbiano ao PVC, alem de melhorar ou manter as propriedades mecanicas da blenda. Processos termo e fotodegradativos podem facilitar o ataque microbiano a matriz polimerica do PVC. O presente trabalho pretende investigar a termo, foto e biotransformacao de filmes de blendas de PVC/PCL 1:1 e 3:1 com fungos de solo (Phanerochaete chrysosporium e Aspergillus fumigatus). As mudancas estruturais foram analisadas atraves da espectroscopia de absorcao no infravermelho (FTIR) e no UV-Visivel e as mudancas morfologicas, atraves de Microscopia Eletronica de Varredura (MEV) / The plastics are one of used the most materials daily. Thus, the plastics wastes have increased considerably and today represent 20% of the waste total volume in the municipal landfills. PVC (poly vinyl chloride) is a synthetic polymer, unstable in the presence of heat and light, that degrades on relative low temperature (approximately 130ºC), and releases HCl. The dehydrochlorination produces new species on polymeric chain, thus, polyenes sequences, that can be checked by the UV-Visible absorption spectroscopy. The recycling of PVC presents some difficulties due its behaviour during the technological processing and its biodegradation is difficult. PCL (polycaprolactone), a synthetic polyester is susceptible to enzymes action, and undergo hydrolysis and degradation. The blend of PVC and PCL can be one way to facilitate the microorganisms attack to the PVC polymer and to improve the mechanical properties of the blend. Thermal and photodegradation process can to facilite the microorganisms attack on PVC polymeric chain. The present work intends to investigate the thermal, photo and biotransformation of polymer films and blends of PVC/PCL 1:1 and 3:1 blends, with soil fungi (Phanerochaete chrysosporium and Aspergillus fumigatus). The structural changes were analysed by infrared absorption spectroscopy (FTIR) and the UV-Visible. The morphologics changes were investigated by scanning electron microscopy (SEM)

Alogliptina (ALG) é um hipoglicemiante oral, que inibe a enzima dipeptidil peptidase – 4 (DPP-4) com alta seletividade e aumenta a secreção de insulina prevenindo a hiperglicemia prandial. Como ALG não está descrita nas farmacopeias, este trabalho objetivou caracterizar a matéria-prima (Capítulo I), desenvolver métodos analíticos (Capítulo II) e avaliar sua estabilidade (Capítulo III), auxiliando no controle de qualidade. No capítulo I, a ALG foi caracterizada através de calorimetria exploratória diferencial (DSC), termogravimetria (TGA) e microscopia eletrônica de varredura (SEM) acoplada a espectrômetro de raios X por dispersão de energia (EDS). A compatibilidade entre a ALG e os excipientes presentes nos comprimidos foi avaliada por DSC, TGA, infravermelho com transformada de Fourier (FTIR), difração de raios-X de pó (XRPD) e microscopia com estágio de aquecimento. ALG apresentou pureza próxima a 99%, com faixa de fusão entre 179,4 e 187,2 °C (pico em 183,3 °C), seguida por decomposição que iniciou em 198,0 °C. Na SEM/EDS, os cristais de ALG mostraram-se predominantemente irregulares e foram detectados traços de impurezas (chumbo e cobre). Alterações na temperatura de fusão da ALG com manitol, estearato de magnésio e nos comprimidos comerciais foram observadas. A microscopia com aquecimento demonstrou que a interação entre manitol e ALG e nos comprimidos é devida à solubilização do fármaco no excipiente fundido, enquanto que na mistura com o estearato de magnésio é devida à fusão do excipiente e do fármaco que ocorrem separadamente, onde o excipiente funde antes que o fármaco. FTIR e XRPD das misturas não detectaram incompatibilidades, somente o aparecimento de bandas adicionais relacionadas aos excipientes. ALG foi compatível com todos os excipientes testados. Estes resultados são importantes para caracterizar, conhecer a estabilidade e a compatibilidade do fármaco. No capítulo II, foram desenvolvidos e validados métodos de cromatografia líquida (LC) indicativos de estabilidade utilizando dois detectores, ultravioleta (UV) e detector de aerossol carregado (CAD) para análise de ALG em comprimidos. Foi utilizada uma coluna C8 (250 mm x 4,6 mm, 5 μm) em modo isocrático, fluxo de 0,8 mL min-1, utilizando acetonitrila e tampão acetato de amônio 10 mM pH 3,5 ajustado com ácido acético (90:10, v/v) como fase móvel e detecção no UV em 275 nm. Os métodos foram lineares no intervalo de 25 - 200 μg mL-1 em ambos os detectores. Os limites de detecção foram de 2,65 e 6,25 μg mL-1 e os de quantificação de 8,84 e 20,85 μg mL-1, respectivamente, para UV e CAD. Os métodos foram precisos e exatos, com desvio padrão relativo menor que 3% e percentuais de recuperação próximos a 100%. Nenhum dos excipientes, ou produtos de degradação interferiu na detecção do fármaco durante os estudos de especificidade. No ensaio de robustez, pequenas alterações no fluxo de fase móvel, pH e concentração de solvente orgânico não afetou significativamente os resultados. O doseamento dos comprimidos obtido com ambos detectores não mostrou diferenças entre si. Os métodos podem ser considerados intercambiáveis e podem ser aplicados como ferramentas para o controle de qualidade de rotina de comprimidos de ALG. No capítulo III foi avaliada a estabilidade térmica da ALG utilizando TGA isotérmica e não isotérmica, e degradação em estufa, analisando as amostras por LC-UV. Na TGA isotérmica a ALG foi submetida a 150, 155, 160, 165, 170 °C, até perda de massa de 10% e os dados foram analisados pelo método de Arrhenius. Na TGA não isotérmica variaram-se as razões de aquecimento, utilizando 2,5, 5,0, 10,0 e 15,0 °C/min até 500 °C. Os dados foram analisados pelo método de Ozawa e de Kissinger. Na degradação em estufa o fármaco foi submetido as temperaturas de 130, 140, 150, 155, 160 e 170 °C. Os parâmetros cinéticos foram obtidos por Arrhenius. ALG segue degradação de zero ordem, onde a velocidade de degradação independe da concentração do reagente. A perda de massa está relacionada à perda química. Os parâmetros cinéticos variaram de acordo com o modelo matemático aplicado. A energia de ativação variou de 26 a 45 kcal/mol. O fármaco degradado demonstrou ser menos tóxico em ensaio de citotoxicidade em células CRIB do que o fármaco não degradado. Os métodos desenvolvidos e a caracterização realizada mostram-se úteis para o adequado controle de qualidade do fármaco. / Alogliptin (ALG) is an oral hypoglycemic agent, which inhibits the enzyme dipeptidyl peptidase - 4 (DPP-4) with high selectivity and increase insulin secretion, preventing postprandial hyperglycemia. ALG is not described in any pharmacopeia. In this context, this study aimed to characterize the active pharmaceutical ingredient (Chapter I), to developed assay methods (Chapter II) and to evaluate the stability (Chapter III), assuring the adequate quality control. In Chapter I, ALG was characterized by differential scanning calorimetry (DSC), thermogravimetry (TGA) and scanning electron microscopy (SEM) coupled with energy dispersive spectrometer X-ray (EDS). The compatibility between ALG and the excipients present in the commercial tablets was evaluated by DSC, TGA, Fourier transform infrared (FTIR), X-ray powder diffraction (XRPD) and hot stage microscopy. ALG presented purity close to 99%, with a melting range between 179.4 to 187.2 °C (peak at 183.33 °C), followed by decomposition which began at 198 °C. In the SEM/EDS the crystals of ALG were predominantly irregulars and it were detected traces of impurities (lead and copper). Alterations in melting temperature of ALG with mannitol, magnesium stearate and in tablets were observed. The hot stage microscopy showed that the interactions between mannitol and ALG and in the tablets were due to the solubilization of the drug in the fused excipient, and in the mixture with magnesium stearate, it was due to the melting of the drug and excipient separately, where the excipient started the melting prior of the drug. FTIR and XRPD of the mixtures did not detect incompatibilities, only the appearance of additional bands related to the excipients. ALG was compatible with all excipients tested. These results are important to characterize, to know the drug stability and compatibility. In Chapter II, liquid chromatography (LC) methods indicative of stability were developed and validated using two detectors, ultraviolet (UV) and charged aerosol detector (CAD) for ALG tablets. It was used a C8 column (250 mm x 4.6 mm, 5 um) in isocratic mode, flow rate of 0.8 ml min-1 using acetonitrile and ammonium acetate buffer 10 mM, pH 3.5 adjusted with acid acetic acid (90:10, v/v) as mobile phase and UV detection at 275 nm. The methods were linear in the range of 25 - 200 μg ml-1 in both detectors. Limits of detection were 2.65 and 6.25 μg mL-1, and of quantification were 8.84 and 20.85 μg mL-1, respectively, for UV and CAD. The methods were accurate and precise, with a relative standard deviation lower than 3% and recovery close to 100%. None of the excipients or degradation products showed interference in the drug detection during specificity studies. In the robustness test, small changes in the mobile phase flow, pH and organic solvent concentration did not significantly affect the results. The results for tablets obtained with both detectors showed no differences. The methods may be considered interchangeable, and they can be used as tools for routine quality control of ALG tablets. In Chapter III the thermal stability of the ALG was evaluated using isothermal and non-isothermal TGA, as well as oven, and samples were analyzed by LC-UV. In the isothermal TGA the ALG was subjected to 150, 155, 160, 165, 170 °C until a mass loss of 10% and the data were analyzed by the Arrhenius method. In non-isothermal TGA the heating rates were varied using 2.5, 5.0, 10.0 and 15.0 °C/min until 500 °C. Data were analyzed by the Ozawa and Kissinger method. In oven the drug was subjected to 130, 140, 150, 155, 160, and 170 °C. The kinetic parameters were obtained by Arrhenius. ALG follows zero-order degradation, where the rate of degradation is independent of the concentration of any reagent. Mass loss is related to chemical reactions. The kinetic parameters varied according to the applied mathematical model. The activation energy ranged from 26 to 45 kcal / mol. The degraded drug was shown to be less toxic in cytotoxicity assay using CRIB cells than the non-degraded drug. The methods developed and the characterization performed proved to be useful for adequate quality control tests of the drug.