Copper (Cu) has been the main choice of the metallization in advanced IC package technology. The epoxy molding compounds (EMC) and the solder flux used in the packaging devices can release ionic impurities. In the halide environment, the electrochemical migration (ECM) failure and corrosion related failure of copper redistribution layer (RDL) and the Cu bond pads respectively was studied. Electrolytic migration arises when the IC package undergoes testing as per JESD22-A110 standards (130oC, 85% RH for 96/256 hrs.). Copper migration is fundamentally an ionic process that requires an electrolyte, moisture, and bias. To accelerate the time for investigating these failures, it was important to benchmark the metrology for real time observation of ECM failure under high voltage. Metrology for electrochemical defect analysis (MEDA) was developed to provide insight on failure mechanism. The Cu RDL on wafer level chip scale package devices were tested by PEG drop test (PDT) using non-aqueous polyethylene glycol (PEG) matrix doped with ions (Cl-, ClO4-, SO4-) to simulate EMC environment. PDT was conducted to analyze the real time migration behavior of Cu electrodes using a potentiostat and microscope. A novel Cu-selective passivation coating was applied on Cu either by wet processes or chemical vapor deposition (CVD) that are IC manufacturing compatible. This Cu-selective passivation coating is thermally stable, strongly adheres to Cu, corrosion resistant, low cost and shows good potential to prevent ECM defects at the high voltage bHAST condition. FTIR and potentiodynamic polarization were utilized to characterize the Cu-selective passivation coating. Statistically union of selected analytical techniques help to acquire unique results about the chemical systems. Together, electrochemistry and spectroscopy help to gather chemical information about the composition near and on the electrode. Additionally, during the SnAgCu (SAC) solder ball bonding on the Cu wafer by mass reflow process, solder flux is used to reduce the native oxides on Cu and SAC solder ball. Post cleaning, residual amount of the solder flux corrodes the Cu wafer. Passivation coating is used as an organic solder preservative to avoid the solder flux while facilitating a good bond between the SAC solder ball and Cu wafer. We investigated the efficiency of the passivation coating in preventing the copper thermal oxidation. The intermetallic compound formation between the Cu wafer and SAC solder ball was studied on 2nm, 6nm, 30nm and 50nm passivated Cu wafer. Based on the SEM/EDS analysis 1.7 µm CuxSny IMC was formed on 2nm coated cu wafer with a Cu:Sn ratio of 1.8:1 & 0.13:1.

Surface catalysed reactions play an important role in chemical productions. Developments of catalyst requiring high activity whilst improving on product selectivity can potentially have a profound effect in the chemical industry. Traditional catalyst modifications were focused on tuning the size, shape and foreign metal doping to form well defined metal nanoparticles of unique functionalities. Here, we show new approach to engineering of metal nanocatalysts via a subsurface approach can modify the chemisorption strength of adsorbates on the surface. Carbon modified nanoparticles were synthesised using glucose to stabilise Pd nanoparticles at a molecular level. Upon heat treatment, the carbonised glucose encapsulated the Pd nanoparticles with carbon atoms take residence in the octahedral holes (15 at.%). These materials were tested in liquid phase stereoselective hydrogenations of 3-hexyn-1-ol and 4-octyne. The former has importance in the fragrance industry towards the production of leaf fragrance alcohol. It was shown for the first time that the geometrically and electronically modified Pd with interstitial carbon atoms reduced the adsorption energy of alkenes, ultimately leading to higher reaction selectivity. Boron modified Pd nanoparticles was synthesised using BH₃.THF in the liquid phase. The material possess high B interstitial saturation (20 at.%), which can be synthesised for the first time below 100°C. These materials were tested in the liquid phase selective hydrogenation of various alkynes and 2-chloronitrobenzene, of which the latter has importance in the pesticides industry. Kinetic modelling on the hydrogenation of 4-octyne suggests these subsurface occupied B does play a pivotal role on increasing the reaction selectivity, as removal of these species lead to decreased selectivity. Au nanoparticles were synthesised and characterised using H¹³COOH NMR. The new liquid NMR characterisation method is successfully applied to examine the chemisorption strength of metal nanoparticles. An attempt to synthesise PVP capped B modified Pd nanoparticles with the above NMR characterisation was investigated. It is believed the examples of subsurface atom modifications as shown here may offer future catalyst developments in this area.

Cette thèse concerne l’étude de phase de séparation de deux polymères thermosensibles connus-poly(N-isopropylacylamide) (PNIPAM) et poly(2-isopropyl-2-oxazoline) (PIPOZ). Parmi des études variées sur ces deux polymères, il y a encore deux parties de leurs propriétés thermiques inexplicites à être étudiées. Une partie concerne l’effet de consolvant de PNIPAM dans l’eau et un autre solvant hydromiscible. L’autre est l’effet de propriétés de groupes terminaux de chaînes sur la séparation de phase de PIPOZ. Pour ce faire, nous avons d’abord étudié l’effet de l’architecture de chaînes sur l’effet de cosolvant de PNIPAMs dans le mélange de méthanol/eau en utilisant un PNIPAM en étoile avec 4 branches et un PNIPAM cyclique comme modèles. Avec PNIPAM en étoile, l’adhérence de branches PNIPAM de à un cœur hydrophobique provoque une réduction de Tc (la température du point de turbidité) et une enthalpie plus faible de la transition de phase. En revanche, la Tc de PNIPAM en étoile dépend de la masse molaire de polymère. La coopérativité de déhydratation diminue pour PNIPAM en étoile et PNIPAM cyclique à cause de la limite topologique. Une étude sur l’influence de concentration en polymère sur l’effet de cosolvant de PNIPAM dans le mélange méthanol/eau a montré qu’une séparation de phase liquide-liquide macroscopique (MLLPS) a lieu pour une solution de PNIPAM dans le mélange méthanol/eau avec la fraction molaire de méthanol entre 0.127 et 0.421 et la concentration en PNIPAM est constante à 10 g.L-1. Après deux jours d’équilibration à température ambiante, la suspension turbide de PNIPAM dans le mélange méthanol/eau se sépare en deux phases dont une phase possède beaucoup plus de PNIPAM que l’autre. Un diagramme de phase qui montre la MLLPS pour le mélange PNIPAM/eau/méthanol a été établi à base de données expérimentales. La taille et la morphologie de gouttelettes dans la phase riche en polymère condensée dépendent de la fraction molaire de méthanol. Parce que la présence de méthanol influence la tension de surface des gouttelettes liquides, un équilibre lent de la séparation de phase pour PNIPAM/eau/méthanol système a été accéléré et une séparation de phase liquide-liquide macroscopique apparait. Afin d’étudier l’effet de groupes terminaux sur les propriétés de solution de PIPOZ, deux PIPOZs téléchéliques avec groupe perfluorodécanyle (FPIPOZ) ou groupe octadécyle (C18PIPOZ) comme extrémités de chaîne ont été synthétisés. Les valeurs de Tc des polymères téléchéliques ont beaucoup diminué par rapport à celle de PIPOZ. Des micelles stables se forment dans des solutions aqueuses de polymères téléchéliques. La micellization et la séparation de phase de ces polymères dans l’eau ont été étudiées. La séparation de phase de PIPOZs téléchéliques suit le mécanisme de MLLPS. Des différences en tailles de gouttelettes formées à l’intérieur de solutions de deux polymères ont été observées. Pour étudier profondément les différences dans le comportement d’association entre deux polymères téléchéliques, les intensités des signaux de polymères correspondants et les temps de relaxation T1, T2 ont été mesurés. Des valeurs de T2 de protons correspondants aux IPOZs sont plus hautes. / This thesis focused on the phase separation of two well-known thermoresponsive polymers, namely PNIPAM (poly(N-isopropylacrylamide)) and PIPOZ (poly(2-isopropyl-2-oxazoline). Despite various studies of the two polymers, two aspects of their thermal properties remained unclear and needed to be investigated. One is the cononsolvency effect of PNIPAM in water and a second water miscible solvent. The other is the effect of the end group properties on the phase separation of PIPOZ. With this in mind, we first studied the effect of the chain architecture on the cononsolvency of PNIPAM in water/methanol mixture, employing a 4-arm star shape PNIPAM and a cyclic PNIPAM as model. Tethering PNIPAM arms to a hydrophobic core resulted in a reduced Tc (cloud point temperature) and a lower phase transition enthalpy change. The Tc of the star shape PNIPAM was inversely dependent on the polymer molecular weight. The dehydration cooperativity was depressed for the star PNIPAM and cyclic PNIPAM due to topological constraints. A study of the effect of polymer concentration on the cononsolvency of PNIPAM in water/methanol mixture revealed a macroscopic liquid-liquid phase separation (MLLPS) for PNIPAM in water/methanol mixtures of methanol molar fraction ranging from 0.127 to 0.421 at a polymer concentration of 10 g·L-1. The turbid suspension of PNIPAM/water/methanol separated into a polymer rich phase coexisting with a polymer poor solution phase after equilibration for two days at room temperature. The phase diagram showing the MLLPS for the PNIPAM/water/methanol mixtures was constructed based on experimental data. The droplets in the condensed polymer rich phase showed a dependence on the methanol molar fraction. Methanol affects the surface tension of the liquid droplets. The slow equilibrium kinetics of PNIPAM phase separation was sped up and a macroscopic liquid-liquid phase separation realized. In order to study the effect of end groups on the solution properties of PIPOZ, two telechelic PIPOZ end capped with perfluorodecanyl groups (FPIPOZ) and octadecyl groups (C18PIPOZ), respectively, were synthesized. The Tc values of the telechelic polymers were greatly reduced after end-functionalization. Stable micelles formed in aqueous solutions of the telechelic polymers. The micellization and phase separation of the telechelic polymers in water were studied. The phase separation of the telechelic PIPOZs in water followed a liquid-liquid phase separation mechanism. Differences in the sizes of droplets formed inside of the two polymer solutions were observed. To further investigate the differences in the association behaviour between the two telechelic polymer, NMR signal intensities and T1 and T2 relaxation times were examined. Higher 1H T2 values were obtained for the IPOZ unit in FPIPOZ than that in C18PIPOZ, indicating a higher mobility of the main chain in the FPIPOZ micelles than that in the C18PIPOZ micelles. Together with the 13C NMR and 19F NMR relaxation studies, we obtained better knowledge of the association properties of the telechelic PIPOZ in water. NMR relaxation studies proved to be efficient way of probing the solution behaviour of the polymers.

L’objectif de cette thèse est de développer une méthode expérimentale permettant de mesurer simultanément des coefficients de co-diffusion dans les zéolithes, pour des mélanges de paraffines en C6 mono et di-branchées, dont les cinétiques de diffusion sont très différentes. Les espèces sont le 2- et le 3-methyl-pentane (2MP et 3MP) et le 2-2- et le 2-3-dimethyl-butane (22DMB et 23DMB) et l'adsorbant est une silicalite. Cette méthode est basée sur la réponse en sortie d’un lit fixe d’adsorbant à une variation cyclique de la composition à son entrée. La conception d’un modèle faisant intervenir des paramètres cinétiques et thermodynamiques a également être effectuée afin de simuler les courbes de perçages des différents constituants en mélange et sur plusieurs cycles. Les conditions expérimentales sont proches des conditions industrielles, à savoir en phase liquide et à fort taux de remplissage de l’adsorbant (185°C et 35 bars) L’écriture d’un modèle de diffusion, basé sur l’équation de Maxwell-Stefan appliquée au "Dusty Gas Model", dans ces conditions de fonctionnement, implique d’introduire des grandeurs volumiques qui permettent de redéfinir les contraintes liées à la saturation de l'adsorbant. De plus, tout en conservant la simplicité du modèle "Single File Diffusion" (pas de contre-diffusion microporeuse), nous avons montré que la prise en compte d’un flux volumique relatif associé au solide permet de conserver l’indépendance des coefficients de diffusion dans le cristal. Les simulations des courbes de perçage – sur un seul cycle pour les molécules rapides et sur plusieurs cycles pour les molécules lentes – indiquent que les coefficients de diffusion des différents isomères suivent l'ordre suivant : D3MP ˜ D2MP > D23DMB > D22DMB, avec un écart de trois ordres de grandeurs entre le 3MP et le 22DMB, ce qui laisse supposer qu'un procédé de séparation basé sur une sélectivité diffusionnelle peut être envisagé. Cependant, les tests de perçage en condition cyclique permettant de caractériser de manière plus précise le système, il a été possible de mettre en évidence une très lente accumulation du 22DMB au cours des cycles sous certaines conditions opératoires, phénomène qui peut s'avérer indétectable sur un faible nombre de cycles et/ou sur le profils de concentration des autres espèces. Ce phénomène a pour conséquence de diminuer les performances de l'adsorbant, aussi bien d'un point de vue capacitif que d'un point de vue sélectif / The aim of this work is to develop a new experimental method in order to determine simultaneously co-diffusion coefficients in zeolites for mixtures of single- and di-branched C6 paraffins, with totally different diffusion kinetics. The species are 2- and 3-methyl-pentane (2MP and 3MP) and 2-2- and 2-3-dimethyl-butane (22DMB and 23DMB) and the adsorbent is a silicalite. This method is based on the output measurement of an adsorbent column subjected to cyclic variations of its input concentration. The analysis of the mixture experimental breakthrough curves, on several cycles, is carried out using a mathematical model, based on Maxwell-Stefan theory of multi-component diffusion, allowing an estimation of thermodynamic and kinetic parameters. The experimental conditions are close to industrial constraints, i.e. at very high adsorption loading, and in the liquid phase (185°C and 35 bars). This requires to develop a modified Maxwell-Stefan diffusion model, applied to the "Dusty Gas Model", including volume constraints in the crystal which implies to redefine the adsorbent saturation. Moreover, while preserving the simplicity of the "Single File Diffusion" model (no counter-diffusion), a relative volumetric flow of the solid is taken into account, allowing to ensure the independence of the diffusion coefficient of each component in the adsorbent. The Maxwell-Stefan diffusion coefficients for the different isomers, obtained from breakthrough curves simulations – on one cycle for fast diffusing species and several cycles for slow molecules – are in the sequence : D3MP ˜ D2MP, > D23DMB > D22DMB, with a difference of three orders of magnitude between 3MP and 22DMB. This implies that a separation process based on kinetic selectivity can be considered. The cyclic breakthrough experiments, allowing a better characterization of the system, highlight a very slow accumulation of the 22DMB isomer during cycles for specific operating conditions, which may be undetectable on a small number of cycles and on the profiles of the other components.. This phenomenon involves a decrease of the adsorbent performances, in terms of capacity as well as selectivity

A mefloquina (MQ), fármaco utilizado na profilaxia e tratamento da malária ocasionada por Plasmodium falciparum resistente à cloroquina, é comercializada na forma racêmica. Apresenta disposição cinética estereosseletiva e ação farmacológica diferencial entre os enantiômeros. A maioria dos métodos analíticos desenvolvidos para análise do fármaco em plasma utiliza como técnicas de preparação das amostras, a extração líquido-líquido ou a extração em fase sólida. Por outro lado, a microextração em fase líquida (LPME), técnica recentemente desenvolvida, pode oferecer resultados bastante satisfatórios para amostras complexas, como fluidos biológicos. Portanto, o presente trabalho teve por finalidade o desenvolvimento e validação de um método analítico empregando a cromatografia líquida de alta eficiência com fases estacionárias quirais juntamente com a LPME para a análise enantiosseletiva da MQ em plasma. Empregando-se a coluna Chiralpak AD com fase móvel constituída por hexano/etanol/DEA (97:3:0,05, v/v/v), obteve-se a separação dos enantiômeros da MQ, com tempos de retenção reduzidos e resolução apropriada. Utilizando-se uma membrana capilar de polipropileno, juntamente com éter diexílico (fase orgânica) e ácido perclórico 10 mmol L-1 (fase aceptora) como componentes do sistema de três fases, obteve-se excelente isolamento dos interferentes endógenos aliado a um enriquecimento satisfatório dos analitos, sendo então possível a validação do método desenvolvido. A metodologia otimizada apresentou linearidade satisfatória no intervalo de 50 ? 1500 ng mL-1 com coeficientes de determinação > 0,998 para ambos enantiômeros. Os valores de recuperação absoluta de (-)-(SR)-MQ e (+)-(RS)-MQ foram 33,2% e 35,0%, respectivamente. Precisão e exatidão, avaliadas por estudos intra-ensaio e interensaio, foram < 15% para ambos enantiômeros. Além disso, não foram observadas racemização ou degradação do fármaco durante a preparação das amostras e análise cromatográfica. Posteriormente, o método desenvolvido e validado foi aplicado em um estudo-piloto de disposição cinética em ratos. Verificou-se que a disposição cinética da MQ em ratos foi estereosseletiva, já que maiores concentrações de (+)-(RS)-MQ foram obtidas em todos os tempos de análise avaliados. / Mefloquine (MQ), a drug used for prophylaxis and treatment of malaria caused by chloroquine-resistant strains of Plasmodium falciparum, is commercialized as a racemic mixture. MQ enantiomers demonstrate differential stereoselective dispositions and pharmacodynamic actions. The majority of methods developed for the determination of mefloquine in plasma includes liquid-liquid or solid-phase extraction as sample preparation. On the other hand, liquid-phase microextraction (LPME), a recently developed technique, may offer satisfactory results for complex matrices, such as biological fluids. Therefore, the aim of this work was to develop and validate an analytical method using chiral high-performance liquid chromatography combined with LPME for the enantioselective analysis of MQ in plasma. Employing a Chiralpak AD column with hexane/ethanol/DEA (97:3:0.05, v/v/v) as mobile phase, separation of MQ enantiomers was achieved with short retention times and appropriate resolution. Using a polypropylene-based capillary membrane together with di-n-hexyl ether (organic phase) and 10 mmol L-1 perchloric acid (acceptor phase) as components of a three-phase system, an excelent clean-up of endogenous interferents, allied with a satisfactory enrichment of analytes, was obtained, which allowed method validation. The optimized methodology exhibited good linearity over a 50 - 1500 ng mL-1 range with correlation coefficients of > 0.998 for both enantiomers. The mean recoveries of (-)-(SR)-MQ and (+)-(RS)-MQ were 33.2 and 35.0%, respectively. Precision and accuracy, demonstrated by within-day and between-day assays, were lower than 15% for both enantiomers. Furthermore, no racemization or degradation were seen during sample preparation and chromatographic analysis. Finally, the developed and validated method was applied to a pilot pharmacokinetic assay in rats. An enantiosselective kinetic disposition of MQ enantiomers was observed in rat plasma, as concentrations of (+)-(RS)-MQ were greater than its antipode at all measured times.

Estudos de metabolismo in vitro possuem o intuito de caracterizar e quantificar possíveis metabólitos, elucidar as vias metabólicas e sugerir modelos a serem seguidos para a realização de estudos in vivo. Com o intuito de estudar o metabolismo in vitro não estereosseletivo da rosiglitazona (RSG) empregando fração microssomal de fígado de ratos,foi desenvolvida uma metodologia por cromatografia líquida de alta eficiência (HPLC) com detecção UV em 245 nm, para analisar a RSG e seus principais metabólitos, p-hidroxi rosiglitazona (?-OH-R) e N-desmetil rosiglitazona (N-Dm-R). Os analitos foram separados em fase reversa, utilizando uma coluna X-Terra MS C-18 (partículas de 3,5 ?m) e fase móvel composta por água:acetonitrila:ácido acético (85:15:0,5, v/v/v), na vazão de 1 mL min-1. Matrizes biológicas contém um grande excesso de proteínas, lipídeos e outros materiais endógenos que interferem na análise de fármacos e metabólitos, tornando necessário um procedimento adequado de preparação das amostras antes da análise cromatográfica. A microextração em fase líquida com membrana cilíndrica oca (HF-LPME) é uma técnica promissora para a preparação de amostras em estudos de metabolismo in vitro, pois, além de promover o clean-up, promove também o enriquecimento dos analitos na amostra. A HF-LPME foi aplicada pela primeira vez para a extração simultânea desse fármaco e seus metabólitos. O sistema de três fases foi escolhido como o mais apropriado, empregando uma solução de ácido clorídrico como fase aceptora e 1-octanol como solvente orgânico. A otimização dos demais parâmetros foi realizada através de planejamento fatorial fracionário. O método foi validado e foi linear no intervalo de 50-6000 ng mL-1, apresentando limites de quantificação de 50 ng mL-1 e recuperações acima de 47 % para a RSG e seus metabólitos (?-OH-R e N-Dm-R). O método validado foi empregado em um estudo de metabolismo in vitro com fração microssomal de fígado de ratos. Nesse estudo, foi possível estimar as constantes de Michaelis-Menten (Km) e a velocidade inicial máxima (Vmax). N-Dm-R e ?-OH-R apresentaram valores de Vmax de 87,30 ± 8,04 e 51,64 ± 12,25 ?mol min-1 mg proteína-1, respectivamente, enquanto que os valores de Km foram de 58,14 ± 11,85 e 77,84 ± 36,77 mmol L-1, respectivamente. Outros metabólitos foram observados nos cromatogramas e a identificação foi feita por espectrometria de massas: ?rto-hidroxi-rosiglitazona e N-desmetil-hidroxi-rosiglitazona. A RSG é comercializada como uma mistura racêmica, apesar de possuir sua atividade antidiabética relacionada essencialmente com o enantiômero (S). O centro quiral desse fármaco possui um grupo carbonila, por isso, o enantiômero (R) pode se converter no enantiômero (S) ou vice-versa, via tautomerismo cetoenólico. Dados da literatura indicavam que essa racemização poderia ser lenta o suficiente para possibilitar o estudo dos enantiômeros isoladamente. Entretanto, até o momento não há dados sobre a disposição cinética ii e metabolismo enantiosseletivos desse fármaco. Sendo assim, propôs-se o desenvolvimento de metodologias analíticas para estudar a racemização da RSG e seus metabólitos e avaliar a possibilidade de estudar seu metabolismo in vitro de forma estereosseletiva. O método foi desenvolvido empregando HPLC com detecção em 245 nm. A separação dos enantiômeros do fármaco e metabólitos, também quirais, foi obtida empregando uma coluna Chiralcel OJ-H e fase móvel constituída por metanol:etanol (90:10; v/v), na vazão de 0,3 mL min-1. O estudo de racemização mostrou que o fármaco e seus metabólitos são racemizados nas condições em que o estudo de metabolismo é conduzido. Finalmente, para estudar o metabolismo in vitro da pioglitazona (PGZ), foi desenvolvido um método para análise desse fármaco e de seus principais metabólitos, a hidroxi-pioglitazona (M-IV) e a ceto-pioglitazona (M-III) empregando a eletroforese capilar (CE). As análises foram realizadas em capilar de sílica de 50 ?m de diâmetro interno e com comprimento efetivo de 40 cm, utilizando tampão fosfato de sódio 50 mmol L-1, pH 2,5, detecção em 190 nm, tensão de 30 kV e temperatura do capilar de 35 °C. A HF-LPME também foi empregada para a preparação das amostras. O sistema de três fases foi escolhido, empregando solução de ácido clorídrico como fase aceptora e o 1-octanol como solvente orgânico. A otimização dos demais parâmetros foi realizada através de planejamento fatorial fracionário. O método validado foi linear no intervalo de 200 - 25000 ng mL-1 para PGZ e 200 - 2000 ng mL-1 para os metabólitos, apresentando limites de quantificação de 200 ng mL-1 e recuperações acima de 19 % para a RSG e seus metabólitos M-IV e M-III. O método validado foi empregado em um estudo de metabolismo in vitro contendo fração microssomal de fígado de ratos, mas nesse estudo, não foi possível observar a formação dos metabólitos. Entretanto, esse método pode ser usado em outros modelos de metabolismo in vitro (microssomas humanos), nos quais se observa a formação desses metabólitos em concentrações maiores. / In vitro metabolism studies have been used to characterize and to quantify possible metabolites, to elucidate metabolic pathways and to suggest models to perform in vivo studies. So the purpose of this study was to evaluate the in vitro rosiglitazone (RSG) metabolism employing microsomal fraction obtained from rat livers. A high- performance liquid chromatography (HPLC) method with UV detection at 245 nm was developed to analyze RSG and the main metabolites, p-hydroxy rosiglitazone (?-OH-R) e N-desmethyl rosiglitazone (N-Dm-R). The analytes were separated under reversed phase conditions, using a X-Terra MS C-18 column (3.5 ?m particle size) and a mobile phase consisting of water:acetonitrile:acetic acid (85:15:0.5, v/v/v), at a flow rate of 1 mL min-1. Biological matrices contain a large excess of proteins, lipids and other endogenous compounds that interfere in the analysis of drugs and metabolites. So, a suitable sample preparation technique is required. Hollow-fiber liquid phase microextraction (HF-LPME) is a promising technique for the preparation of biological samples. Besides the clean-up, analytes enrichment is also achieved. HF-LPME for the simultaneous analysis of RSG and its main metabolites is described for the first time. The three-phase extraction was performed using hydrochloride acid solution as acceptor phase and 1-octanol as organic solvent. The other parameters were optimized by fractional factorial design. The method was validated and it was linear over the concentration range of 50-6000 ng mL-1, with quantification limits of 50 ng mL-1 and recoveries above 47 %. The validated method was used to estimate Michaelis-Menten (Km) constant and maximum initial velocity (Vmax). N-Dm-R e ?-OH-R showed Vmax values of 87.30 ± 8.04 and 51.64 ± 12.25 ?mol min-1 mg protein-1, respectively, while the Kmvalues were 58.14 ± 11.85 e 77.84 ± 36.77 mmol L-1, respectively. Other possible metabolites were observed in the chromatograms and they were identified by mass spectrometry: ?rtho-hydroxy-rosiglitazone e N-desmethyl-hydroxy-rosiglitazone. RSG is marketed as a racemic mixture although the antidiabetic activity is related essentially to the (S)-enantiomer. The chiral center has a carbonyl group, therefore the (R)-enantiomer could be transformed to the (S)-enantiomer or vice-versa by keto-enolic tautomerism. The literature indicates that this racemization is slow enough to allow the evaluation of the properties of the isolated enantiomers. However, there is no information in the literature about enantioselective RSG kinetic disposition and metabolism. Considering this facts, an analytical procedure was developed to study the racemization of RSG and its metabolites under different conditions and to determine if the enantioselective metabolism would be performed. The method was developed by HPLC with detection at 245 nm. The chiral separation of RSG and metabolites was achieved on a Chiralcel OJ-H column, with the mobile phase consisting of methanol:ethanol (90:10,v/v). The results obtained showed that the racemization occurs under the conditions used in in vitro iv metabolism studies. Finally, to study the in vitro metabolism of pioglitazone (PGZ), another method was developed by capillary electrophoresis (CE) to determine this drug and its main metabolites, hydroxy-pioglitazone (M-IV) and keto-pioglitazone (M-III). The analyses were conducted using a fused silica capillary (50 ?m inner diameter and 40 cm effective length), sodium phosphate buffer 50 mmol L-1, pH 2.5, detection at 190 nm, voltage of 30 kV and capillary temperature of 35°C. HF-LPME was also used for sample preparation with hydrochloride acid solution as acceptor phase and 1-octanol as organic solvent. The other parameters were optimized by fractional factorial design. The method was validated showing to be linear in the concentration range of 200 - 25000 ng mL-1 for PGZ and 200 - 2000 ng mL-1 for the metabolites. Quantification limits were 200 ng mL-1 for all analytes and the recoveries were higher than 19%. The validated method was used to study the in vitro metabolism of PGZ by rat liver microsomal fraction, but it was not possible to observe the formation of the metabolites in this study. However this method could be used in other in vitro metabolism models (human microssomes), in which higher concentrations of these metabolites are observed. Keywords:

As drogas facilitadoras de crime (DFC) são uma série de substâncias químicas que permitem o ato sexual e/ou roubo com pouca ou nenhuma resistência da vítima. Benzodiazepínicos, gama-hidroxibutirato (GHB), cetamina e etanol são clássicas DFC, porém outras substâncias também têm sido utilizadas. Devido às diferentes classes de DFC e a necessidade de métodos sensíveis, a determinação dessas substâncias é um desafio aos toxicologistas forenses. A proposta do estudo foi desenvolver métodos analíticos para determinação principais analitos alvos de DFC para benzodiazepínicos, cetamina e GHB em amostras de urina. Esta matriz biológica é considerada uma amostra não-invasiva e apresenta um período de detecção maior que o sangue. A preparação das amostras foi avaliada através de microextração em fase líquida (LPME) e extração líquido-líquido (LLE). A LPME é uma técnica de extração de drogas que utiliza menor quantidade de solventes orgânicos, maior praticidade e possibilidade de obtenção de altos valores de recuperação. Os analitos foram determinados por cromatografia gasosa acoplada à espectrometria de massas (GC-MS). A LPME validada para benzodiazepínicos e seus produtos de biotransformação exigiu uma combinação de solventes e dupla derivatização para atingir a sensibilidade exigida, enquanto o método para determinação de cetamina, norcetamina e deidronorcetamina utilizou óleo essencial de eucalipto como meio extrator, caracterizando-se um procedimento ecologicamente correto com alta sensibilidade. A extração de GHB foi efetiva por LLE com redução da quantidade de solvente e tempo de análise sem o prejuízo na sensibilidade. Em geral, os métodos desenvolvidos neste trabalho são sensíveis e confiáveis para todos os analitos relatados e conclui-se que a LPME é uma técnica de preparo de amostra eficiente, versátil de baixo custo. Estas condições permitem que sua implementação em qualquer laboratório de análises toxicológicas, podendo ser aplicada em situações de DFC ou de qualquer outra natureza. / Drug-facilitated crime (DFC) are a series of chemicals that allow the sexual act and/or theft with little or no resistance from the victim. Benzodiazepines, gamma-hydroxybutyrate (GHB) and ketamine and ethanol are considered classic DFC, however other substances were also used as the DFC. Due to the different classes of DFC and the need for sensitive methods, the determination of these substances is a challenge to forensic toxicologists. The purpose of this study was to develop analytical methods for determination of the main target analytes of DFC for benzodiazepines, ketamine and GHB in urine samples. This biological matrix is considered a non-invasive sample and shows a larger window of detection than blood. Sample preparation was assessed using liquid phase microextraction (LPME) and liquid-liquid extraction (LLE). The LPME is a drug extraction technique that uses less organic solvents, greater practicality and possibility of obtaining high recovery values. The analytes were determined by gas chromatography - mass spectrometry (GC-MS). The validated LPME technique for benzodiazepines and their metabolites required a combination of solvents and double derivatization to achieve the required sensitivity, while the ketamine, norketamine and dehydronorketamine method used essential oil of eucalyptus as solvent, characterizing a green chemistry approach with high sensitivity. The extraction of GHB was effective by LLE with a reduced amount of solvent and the analysis time without loss in sensitivity. In general, the methods developed in this work using GC-MS are sensitive and reliable for all analytes reported and LPME technique showed to be an efficient sample preparation, versatile and low cost. These conditions allow LPME implementation in any laboratory of toxicological analysis and it can be applied in situations of DFC or any other kind of analysis.

A análise estereosseletiva tem um lugar de destaque em várias áreas e, dentre elas, a farmacêutica, pois diversos fármacos quirais são comercializados como misturas racêmicas. A análise estereosseletiva empregando a cromatografia líquida de alta eficiência e a eletroforese capilar é prática e bastante eficaz para aplicações que envolvem a determinação de enantiômeros ao nível de traços em matrizes complexas, como por exemplo, em estudos de disposição cinética. Entretanto, devido à complexidade das matrizes biológicas, há necessidade da preparação da amostra antes de sua análise. Entre as diversas técnicas existentes, as mais utilizadas são a extração líquido-líquido e a extração em fase sólida. Contudo, essas técnicas apresentam algumas desvantagens,sendo a principal delas o uso de grandes quantidades de solventes. Portanto, técnicas que requerem pouco ou nenhum consumo de solventes orgânicos são bastante desejáveis. Entre essas técnicas destacam-se a microextração em fase sólida (SPME) e a microextração em fase líquida (LPME). Essas técnicas relativamente recentes têm como vantagens a utilização de quantidades mínimas de solventes orgânicos, o alto poder de concentração, a remoção dos interferentes da matriz biológica e a simplicidade de automação. Nesse trabalho propusemos a utilização da SPME e LPME como técnicas de preparação de amostras de urina, visando o desenvolvimento de métodos estereosseletivos com detectabilidade e seletividade adequadas para aplicação em estudos posteriores de disposição cinética. A SPME foi empregada para análise estereosseletiva do ibuprofeno e de seus principais metabólitos, carboxiibuprofeno e 2-hidroxiibuprofeno e da hidroxicloroquina e seus principais metabólitos, enquanto que a LPME foi usada para a análise estereosseletiva da hidroxicloroquina e seus metabólitos. Inicialmente, foi realizada a otimização da separação dos fármacos e metabólitos em diversas colunas quirais,a otimização da separação da hidroxicloroquina e seus metabólitos por eletroforese capilar e,em seguida, a otimização dos procedimentos de extração e a validação dos métodos desenvolvidos. Utilizando a coluna Chiralpak AD-RH® e fase móvel composta por solução de ácido fosfórico 1 mol L-1 pH 3 : metanol (75 : 25, v/v), foi validado um método para análise enantiosseletiva do ibuprofeno em urina. A SPME foi empregada para extração do ibuprofeno das amostras de urina utilizando a fibra PDMS-DVB 60 6;m. O método mostrou ser linear na faixa de concentração de 0,25 a 25 &#956;g mL–1 para cada enantiômero. Para a análise do 2-hidroxiibuprofeno e carboxiibuprofeno, foi utilizada a coluna Chiralpak AS® e fase móvel composta por hexano: isopropanol (94 : 6, v/v) + 0,05% de ácido trifluoracético. A extração desses metabólitos foi feita empregando a fibra de CW-TPR 50 µm. O método mostrou ser linear na faixa de concentração de 5 a 50 µg mL -1. Já para a análise da hidroxicloroquina e seus principais metabólitos, DHCQ e DCQ, foi utilizada a coluna Chiralcel OD-H® e fase móvel composta por hexano : etanol : metanol (96 : 2 : 2, v/v/v) + 0,2% de dietilamina. A extração desses metabólitos foi feita empregando a fibra de PDMSDVB 60 &#956;m. O método mostrou ser linear na faixa de concentração de 50 a 1000 ng mL -1para HCQ e 42 - 416 ng mL-1 para os metabólitos. A microextração em fase líquida foi avaliada na análise da hidroxicloroquina e seus metabólitos, BDCQ, DHCQ e DCQ e separação por eletroforese capilar. Para tanto foi utilizado um capilar de sílica fundida nãorecoberto com um comprimento efetivo de 42 cm, e 30 mmol L-1 de HP-b-CD + 1% de CD-b- sulfatada dissolvida em tampão tris(hidroxiaminometano) 100 mmol L-1 pH 9 como tampão de análise. O método mostrou ser linear na faixa de concentração de 10 - 1000 ng mL-1 para HCQ e 21-333 ng mL-1 para os metabólitos. Obteve-se precisão com coeficientes de variação inferiores a 15% e exatidão com erros relativos menores que 15% para todos os métodos desenvolvidos. Após validação, os métodos foram empregados na determinação da quantidade excretada acumulada do do ibuprofeno, da hidroxicloroquina e de seus metabólitos após administração de de rac-ibuprofeno e rac-hidroxicloroquina a voluntários sadios. Em suma, as duas técnicas foram eficientes na extração dos fármacos e metabólitos estudados. A SPME mostrou ser uma técnica de mais fácil manuseio, porém com baixos valores de recuperação. Por outro lado, a LPME apresentou valores de recuperação maiores, porém o manuseio do sistema de extração foi mais difícil, necessitando de um tempo maior para o domínio da técnica. / The stereoselective analysis has been standing out in several areas, and it is mainly present in the pharmaceutical industry, since many drugs are marketed as racemic mixtures. The stereoselective analysis employing high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) is very useful for the determination of enantiomers at very low concentrations, as the ones found in biological matrices, for instance, in pharmacokinetic studies. The first step in the analysis of drugs in biological fluids is the extraction procedure. The most common extraction procedures employed are liquid-liquid extraction and solidphase extraction. These techniques show several drawbacks, such as the high amount of organic solvent consumed. So, based on this fact, techniques that consume small amounts of organic solvents are desirable. Among these techniques, solid-phase microextraction (SPME) and liquid-phase microextraction (LPME) have been stood out. The main advantages of these techniques are the small amount of organic solvent consumed and its high capacity in drug concentration. In this work, our purpose was to employ the SPME and the LPME as sample preparation techniques to develop stereoselective methods to be further applied in pharmacokinetic studies. SPME was employed for the stereoselective analysis of ibuprofen, hydroxychloroquine and their major metabolites.On the other hand,LPME was employed only for the enantioselective analysis of hydroxychloroquine and its metabolites. The first step was the separation optimization of the drugs and their metabolites by HPLC using several chiral columns, and the separation optimization of hydroxychloroquine and its metabolites by CE. Next, the extraction optimizations and method validations were performed. The enantioselective analysis of ibuprofen in human urine was carried out in the Chiralpak AD-RH® column, using methanol-pH 3.0 phosphoric acid solution (75 : 25 v/v) as mobile phase. The method was linear over the 0.5 - 25 µg mL-1 concentration range for both enantiomers. The fiber used in this method was PDMS-DVB 60 µm.The analysis of 2-hydroxyibuprofen and carboxyibuprofen was performed on a Chiralpak AS® column using hexane:isopropanol (95 : 5 v/v) plus 0.05% trifluoroacetic acid as the mobile phase. The method was linear over the 5 - 50 µg mL-1 concentration range. To perform the extractions, a CW-TPR 50 µm coated fiber was employed. The analysis of hydroxychloroquine and its major metabolites (DCQ and DHCQ) was done on a Chiralcel OD-H® column using hexane-methanol-ethanol (96 : 2 : 2, v/v/v) plus 0.2% diethylamine as mobile phase. The extraction was performed using a PDMS-DVB 60 µm coated fiber. The method was linear over the range of 50 - 1000 ng mL-1 for HCQ enantiomers and over the range of 42 - 416 ng mL-1 for DCQ and DHCQ enantiomers. LPME and CE were applied for the chiral determination of hydroxychloroquine and its metabolites (DCQ, DHCQ, BDCQ) in human urine. The electrophoretic separations were carried out in 100 mmol L-1tris(hydroxymethyl)aminomethane buffer (pH adjusted to 9.0 with phosphoric acid) containing 1% (w/v) S-b-CD and 30 mg mL-1 HP-?-CD, with a constant voltage of +18 kV. The method was linear over the concentration range of 10-1000 ng mL -1 for each HCQ stereoisomer and 21-333 ng mL -1 for each metabolite stereoisomer. Within-day and between-day assay precision and accuracy for all described methods were lower than 15%. The developed methods were applied for the determination of the cumulative urinary excretion of ibuprofen metabolites and hydroxychloroquine and its metabolites after oral administration of racibuprofen and rac-hydroxychloroquine to health volunteers. Comparing the techniques, both SPME and LPME were efficient to extract the drugs and their metabolites from human urine. iv SPME showed to be an easier technique to handle, however, the drug amount recovered by this technique was too small. On the contrary, LPME was a more difficulty technique to be handled, but better recovery values were obtained with this technique.

Das Hochtemperaturverhalten beeinflusst viele verschiedene Prozesse von der Materialherstellung bis hin zur technologischen Anwendung. In-situ Transmissionselektronenmikroskopie (TEM) bietet die Möglichkeit, die atomaren Prozesse während struktureller Phasenübergänge direkt und in Realzeit zu beobachten. In dieser Arbeit wurde in-situ TEM angewendet, um die Reversibilität des Schmelz- und Kristallisationsprozesses, sowie das anisotropen Sublimationsverhaltens von Ge-Sb-Te (GST) Dünnschichten zu untersuchen. Die gezielte Probenpräparation für die erfolgreiche Beobachtung der Hochtemperatur-Phasenübergänge wird hervorgehoben. Die notwendige Einkapselung für die Beobachtung der Flüssigphase unter Vakuumbedingungen und die erforderliche sauberer Oberfläche für den Sublimationsprozess werden detailliert beschrieben. Außerdem wird die Elektronenenergieverlustspektroskopie eingesetzt um die lokale chemische Zusammensetzung vor und nach den Übergängen zu bestimmen. Die Untersuchung der Grenzflächenstruktur und Dynamik sowohl beim Phasenübergang fest-flüssig als auch flüssig-fest zeigt Unterschiede zwischen den beiden Vorgängen. Die trigonale Phase von GST weist beim Schmelzen eine teilweise geordnete Übergangszone an der fest-flüssig-Grenzfläche auf, während ein solcher Zwischenzustand bei der Erstarrung nicht entsteht. Außerdem läuft der Schmelzvorgang zeitlich linear ab, während die Kristallisation durch eine Wurzelabhängigkeit von der Zeit mit überlagerter Start-Stopp-Bewegung beschrieben werden kann. Der Einfluss der Substrat-Grenzfläche wird diskutiert und die Oberflächenenergie von GST bestimmt. Die anisotrope Dynamik führt beim Phasenübergang fest-gasförmig der kubischen Phase von GST zur Ausbildung stabiler {111} Facetten. Dies erfolgt über die Bildung von Kinken und Stufen auf stabilen Terrassen. Die Keimbildungsrate und die bevorzugten Keimbildungsorte der Kinken wurden identifiziert und stimmen mit den Voraussagen des Terrassen-Stufen-Kinken Modells überein. / High-temperature behavior influence many different processes ranging from material processing to device applications. In-situ transmission electron microscopy (TEM) provides the means for direct observation of atomic processes during structural phase transitions in real time. In this thesis, in-situ TEM is applied to investigate the reversibility of the melting and solidification processes as well as the anisotropic sublimation behavior of Ge-Sb-Te (GST) thin films. The purposeful sample preparation for the successful observation of the high-temperature phase transitions is emphasized. The required encapsulation for the observation of the liquid phase inside the vacuum conditions and the necessary clean surface for sublimation process are discussed in detail. Additionally electron energy-loss spectroscopy in the TEM is used to determine the local chemical composition before and after the phase transitions. The analysis of the interface structure and dynamic during the solid-to-liquid as well as the liquid-to-solid phase transition shows differences between both processes. The trigonal phase of GST exhibits a partially ordered transition zone at the solid-liquid interface during melting while such an intermediate state does not form during solidification. Additionally the melting process proceeds with linear dependence on time, whereas crystallization can be described as having a square-root time-dependency featuring a superimposed start-stop motion. The influence of the interface is addressed and the surface energies of GST are determined. The anisotropic dynamic of the solid-to-gas phase transition of the cubic GST phase leads to the formation of stable {111} facets. This happens via kink and step nucleation on stable terraces. The nucleation rates and the preferred kink nucleation sites are identified and are in accordance with the predictions of terrace-step-kink model.

Este trabalho avaliou o desempenho de um sistema que combina os processos anaeróbio e aeróbio, para tratamento de esgoto sanitário, operado de modo contínuo sem e com recirculação da fase líquida. A combinação dos processos anaeróbio e aeróbio tem como objetivo aproveitar as vantagens de cada um, minimizando seus aspectos negativos. Foi utilizado um reator, em escala de bancada, de leito fixo e fluxo contínuo de escoamento ascendente com argila expandida e espuma de poliuretano como suportes de imobilização da biomassa. O desempenho do sistema foi avaliado em três diferentes tempos de detenção hidráulica (TDH), 6, 8 e 10 horas, na fase anaeróbia, nos quais os melhores valores de remoção de matéria orgânica chegaram a 80%, com valores de DQO efluente abaixo de 150 mg/L. Com a inserção da fase aeróbia ao sistema (TDH de aproximadamente 11 horas, sendo 8 horas para a fase anaeróbia e 3 horas para a fase aeróbia), a eficiência subiu para mais de 90% com DQO efluente abaixo dos 50 mg/L. A nitrificação ocorreu perto do 15° dia operacional do sistema combinado e estava praticamente estável ao fim dessa etapa operacional. Após o 20º dia de operação as concentrações de nitrito mantiveram-se sempre baixas, o que indica equilíbrio da nitrificação. Foram obtidos ganhos quando feita recirculação do efluente tratado, principalmente em relação à remoção de matéria orgânica (95%) e remoção de nitrogênio total que foi de 75% para razão de recirculação de 1,5. O reator avaliado apresentou estabilidade operacional, alta remoção de matéria orgânica e nitrogênio sem a necessidade de adição de fonte exógena de carbono e de suplementação de alcalinidade. / This work evaluated the performance of a system that combines anaerobic and aerobic processes, for treatment of domestic sewage. The bench-scale fixed-film reactor was operated in a continuous way without and with recycle of the liquid phase. Expanded clay and polyurethane foam were used as supports for immobilization of the biomass. Initially, the system was operated under anaerobic condition and its performance was evaluated for three different hydraulic retention times (HRT), 6, 8 and 10 h. In this phase, COD removal efficiency of 80% was reached for HRT of 10 h, with effluent COD below 150 mgCOD/L. The combined anaerobic-aerobic operation (HRT of approximately 11 h, being 8 h for the anaerobic phase and 3 h for the aerobic phase) favored the organic matter removal that reached 90%, with effluent COD below 50 mgCOD/L. The operation with liquid recycle provided the best results with COD removal of 95% and total nitrogen removal of 75% under recycle ratio of 1.5. The anaerobic-aerobic fixed bed reactor, with recycle of the liquid phase, proved to be an excellent alternative for domestic sewage treatment, mainly when organic matter and nitrogen removals are required. The concomitant C and N removal without addition of exogenous source electron donor and with no additional alkalinity supplementation was the main advantage of this reactor over the conventional reactors applied for this purpose.