The thesis is focused on the development of the electrochemical system with microfluidic platform for the detection of multiple biomarkers. It analyses the use of biomarkers for the early diagnosis of cancer. The theoretical part contains basic information about voltammetric methods and microfluidic systems. The practical part provides solutions to the microfluidic chips, including the description of the used materials, designs, methodologies of preparation and conclusions from the testing of the manufactured microfluidic systems. The thesis describes the lock-in electrochemical system which measures the response of 4 electrochemical cells simultaneously. For the electrochemical system measurements, an electrochemical chip consisting of 64 electrochemical cells was used. The results of the analysis include the processing of the system tests and detected voltammetric curves of the Fe2+/Fe3+ solution and cysteine.

There is a high demand for implementing simulations in the design and product devel-opment processes, avoiding the execution of costly tests on prototypes and giving thechance of discarding unsuitable designs, as well as exploring possible ones without much cost added.This project assignment is to find a suitable way to simulate drop tests on two typesof PMMA sheets, a material widely used on luminaire covers. Therefore, it becomesnecessary to study the mechanical behavior of these materials, using experimental tests,in order to calibrate the material models used in the simulations.During the experimental testing, common polymer behaviors were found on the twostudied materials, such as rate dependence, non-linear elasticity, viscoelasticity and vis-coplasticy. Behaviors which presented several challenges regarding the choice and cali-bration of the material models.The two di?erent polymers were calibrated for the simulations using two di?erentmaterial models. An elastic-plastic (Drucker Prager Plasticity) model was used for oneof the materials, whereas an hyperelastic-viscoelastic model was used for the other one.Finally, several drop tests simulations were conducted and compared with experimentaltests

Amine transaminases (ATA) catalyse the transfer of an amino group from one molecule and replaces a ketone or aldehyde with the amino group, the amino group on the amino-donor is replaced with a ketone or aldehyde. This enzyme, ATA from Chromobacterium violaceum, has previously been used to catalyse the reaction involving amphetamine, therefore, it might be possible to use this enzyme to convert amphetamine and the product absorbs in the UV spectrum and can therefore be measured spectrophotometrically. The aim of the project was to explore the possibility of using ATA in a portable biosensor for the detection of amphetamine. A literature study of commercially available portable biosensors was performed, activity of the free enzyme was tested against two substrates, methylbenzylamine (MBA) and amphetamine. Research on immobilization techniques, materials, and surface functionalization was done to chose suitable methods for immobilizing ATA. Two immobilization methods were suggested and one of the methods, ionic immobilization through His-tag towards Ni2+ on the surface, was tested for enzyme activity toward MBA. The enzyme activity of the free enzyme in solution towards MBA was comparable to previously reported enzyme activity, however, no enzyme activity towards amphetamine was observed. No activity was observed for the immobilized enzyme, but it might be due to the experimental design, more experiments need to be performed to draw conclusions. / Amintransaminaser (ATA) katalyserar överförandet av en amingrupp från en molekyl och ersätter en keton eller aldehyd med den amingruppen, amingruppen på amin-donatorn ersätts med en keton eller aldehyd. Det här enzymet, ATA från Chromobacterium violaceum (CvATA), har tidigare använts för att katalysera en reaktion som involverar amfetamin, därför skulle detta enzym kunna användas på amfetamin. Produkten av reaktionen absorberar i UV spektrumet och kan mätas med en spektrofotometer. Målet med projektet var att utforska möjligheten av att använda CvATA i en biosensor för att detektera amfetamin. En litteraturstudie på kommersiellt tillgängliga bärbara biosensorer genomfördes, aktiviteten av det fria enzymet testades mot två substrat, metylbenzylamin (MBA) och amfetamin. Information samlades om immobiliseringstekniker, material, och ytfunktionalisering gjordes för att välja ut lämpliga metoder för immobilisering av CvATA. Två immobiliseringsmetoder föreslogs och en av metoderna, immobilisering via enzymets His6-tagg och Ni2+ joner på ytan, testades för enzymaktivitet mot MBA. Enzymaktiviteten av det fria enzymet i lösning mot MBA var i samma storleksordning som tidigare rapporterad enzymaktivitet, men ingen enzymaktivitet mot amfetamin kunde observeras. Ingen aktivitet kunde observeras för det immobiliserade enzymet, men det kan vara på grund av designen på experimentet, fler experiment behöver göras för att kunna dra några fler slutsatser.

The advent of ultrafast lasers has enabled micromachining schemes that cannot be achieved by other current techniques. Laser direct writing has emerged as one of the possible routes for fabrication of optical waveguides in transparent materials. In this thesis, the advantages and limitations of this technique are explored. Two extended-cavity ultrafast lasers were built and characterized as the laser sources for this study, with improved performance over existing systems. Waveguides are fabricated in oxide glass, chalcogenide glass, and polymers, these being the three major classes of materials for the telecommunication industry. Standard waveguide metrology is performed on the fabricated waveguides, including refractive index profiling and mode analysis. Furthermore, a finite-difference beam propagation method for wave propagation in 3D-waveguides is proposed. The photo-structural modifications underlying the changes in the material optical properties after exposure are investigated. The highly nonlinear processes of the light/matter interaction during the writing process are described using a free electron model. UV/visible absorption spectroscopy, photoluminescence spectroscopy and Raman spectroscopy are used to assess the changes occurring at the atomic level. Finally, the impact of laser direct writing on nonlinear waveguide applications is discussed.

The aim of the study was to investigate the effect of X-rays used in micro X-ray computer tomography (µXCT) on the mechanical performance and microstructure of a variety of dental materials. Standardised bending beams (2 × 2 × 25 mm3) were forwarded to irradiation with an industrial tomograph. Using three-dimensional datasets, the porosity of the materials was quantified and flexural strength was investigated prior to and after irradiation. The thermal properties of irradiated and unirradiated materials were analysed and compared by means of differential scanning calorimetry (DSC). Single µXCT measurements led to a significant decrease in flexural strength of polycarbonate with acrylnitril-butadien-styrol (PC-ABS). No significant influence in flexural strength was identified for resin-based composites (RBCs), poly(methyl methacrylate) (PMMA), and zinc phosphate cement (HAR) after a single irradiation by measurement. However, DSC results suggest that changes in the microstructure of PMMA are possible with increasing radiation doses (multiple measurements, longer measurements, higher output power from the X-ray tube). In summary, it must be assumed that X-ray radiation during µXCT measurement at high doses can lead to changes in the structure and properties of certain polymers.

No description available.

No description available.

Die vorliegende Arbeit beschreibt die Übertragung der aus der Siliziumtechnologie bekannten Präzision der Strukturierung und die Zuverlässigkeit der Verbindungstechnologie auf andere Materialien wie Kupfer und PMMA. Diese Untersuchung ist auf die Entwicklung der Teiltechnologien Strukturierung und Integration fokussiert und konzentriert sich insbesondere auf die Kombination von Mikrostrukturierung und dreidimensionalen Aufbautechniken einschließlich vertikaler fluidischer Durchkontaktierungen bei den Materialien Silizium, Kupfer und Kunststoff (PMMA). Eine begleitende Charakterisierung und messtechnische Bewertung gestattet die Weiterentwicklung während der Experimentedurchführung und erweitert den Stand der Wissenschaft hinsichtlich der genannten Kombinationen. / The work describes the transfer of well known high precisive and reliable micro technologies for patterning and packaging of Silicon to new materials like Copper and PMMA. This investigation is focused on special patterning technologies and system integration aspects. Furthermore the development of material-dependent micro patterning technologies and multi layer packaging techniques including vertical fluidic interconnects using materials like Silicon, Copper, and PMMA (polymer) is shown. An accompanying characterization and measurement-based evaluation enables the ongoing development while performing experimental analysis. At least a higher state of the art for these complex combinations is reached.

Ces dix dernières années, les technologies de stockage non-volatile Flash ont joué un rôle majeur dans le développement des appareils électroniques mobiles et multimedia (MP3, Smartphone, clés USB, ordinateurs ultraportables…). Afin d’améliorer davantage les performances, augmenter les capacités et diminuer les coûts de fabrication, de nouvelles solutions technologiques sont aujourd’hui étudiées pour pouvoir compléter ou remplacer la technologie Flash. Citées par l’ITRS, les mémoires résistives polymères présentent des caractéristiques très prometteuses : procédés de fabrication à faible coût et possibilité d’intégration haute densité au dessus des niveaux d’interconnexions CMOS ou sur substrat souple. Ce travail de thèse a été consacré au développement et à l'étude des mémoires résistifs organiques à base de polymère de poly-méthyl-méthacrylate (PMMA) et de molécules de fullerènes (C60). Trois axes de recherche ont été menés en parallèle: le développement et la caractérisation physico-chimique de matériaux composites, l’intégration du matériau organique dans des structures de test spécifiques et la caractérisation détaillée du fonctionnement électrique des dispositifs et des performances mémoires. / Over the past decade, non-volatile Flash storage technologies have played a major role in the development of mobile electronics and multimedia (MP3, Smartphone, USB, ultraportable computers ...). To further enhance performances, increase the capacity and reduce manufacturing costs, new technological solutions are now studied to provide complementary solutions or replace Flash technology. Cited by ITRS, the polymer resistive memories present very promising characteristics: low cost processing and ability for integration at high densities above CMOS interconnections or on flexible substrate. This PhD specifically focused on the development and study of composite material made of Poly-Methyl-Methacrylate (PMMA) polymer resist doped with C60 fullerene molecules. Studies were carried out on three different axes in parallel: Composite materials development & characterization, integration of the organic material in specific test structure and advanced devices and finally detailed electrical characterization of memory cells and performances analysis.

Electrophoretic microsystems (EM) are powerful tools for the separation of species of microsystems analyzes which can easily be combined with electrochemical detection (ECD) and therefore making it ideal for a method of detection. However, the influence of high voltage at the working electrode used for the separation is a problem to be overcome due to the increased signal/noise ratio and possible damage of the electrode and/or the potentiostat. Thus, it was proposed in this thesis one EM hybrid PDMS / glass configuration with dual-channel potentiostat coupled to an electrically isolated in order to minimize the influence of high potential in the separation channel and improve the separation efficiency of the species and subsequently, improve detection limits. The EM contains two separate parallel channels 200 microns and a channel separation and another reference, and each containing a platinum electrode 15 or 50 μm placed about 1 to 4 μm in the channel. An electrode served as the working electrode, positioned in the separation channel, and another electrode as reference electrode, placed in the reference channel. This configuration associated with the electrically isolated potentiostat allowed the amperometric signals were measured without any change or potential interference arising from the high voltage applied separation. Aiming to evaluate the effectiveness of the methodology proposed in this thesis, samples nitrite, tyrosine and peroxynitrite (reactive nitrogen species – RNS), hydrogen peroxide (reactive oxygen species – ROS), ascorbic acid, glutathione and cysteine were injected into the channel containing the working electrode, while simultaneously boric acid buffer pH 11 containing TTAB was injected into the reference channel containing the reference electrode. From this configuration, we obtained a significant reduction in noise level (about 0.94 pA) and a relative improvement in the resolution ratified by electropherograms, compared with using single channel configuration. The limits of detection (LOD) for the chemical species mentioned above were 0.58 μM, 0.14 μM, 0.75 μM, 0.21 μM, 0.82 μM, was not obtained for cysteine and 1.63 μM, respectively. The efficiency can also be seen by analyzing nitrite performed on samples of perfusate blood of sheeps and rats, where have been detected a concentration of 68.05 μM and 22.04 μM, respectively, by the proposed method. It was also proposed in this thesis, microfabrication and evaluation of a PMMA electrophoretic microsystem with single channel configuration coupled to a base made of the same material to fix the microchip with electrochemical detection using a carbon paste electrode. The purpose of the construction of the base was to obtain, by fixing, reproducibility of events. And the microfabrication of PMMA EM aimed the viability of its use in analysis perspective as having the lowest cost per unit made due to the use of CO2 laser for microfabrication, which has a value considerably lower, compared with photolithographic processes. The evaluation of this system was performed through the analysis standards of serotonin and acetaminophen, which proved that the microfabrication of this system showed good reproducibility and repeatability of events, making it viable processing. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os microssistemas eletroforéticos (MSE) são ferramentas poderosas para a separação de espécies em microssistemas de análises, onde pode ser facilmente combinada com detecção eletroquímica (DEQ) e tornando-se, portanto, um método de detecção ideal. No entanto, a influência da alta tensão no eletrodo de trabalho utilizada para a separação é um problema a ser contornado devido o aumento da relação sinal/ruído e possíveis danificações do eletrodo e/ou do potenciostato. Assim, foi proposto nesta tese um MSE híbrido de PDMS/vidro com configuração de duplo-canal acoplado a um potenciostato eletricamente isolado com objetivo de minimizar a influência do elevado potencial no canal de separação e melhorar a eficiência de separação das espécies e, subsequentemente, melhorar os limites de detecção. O MSE contém dois canais paralelos separados 200 μm, sendo um canal de separação e outro de referência, e cada um deles contendo um eletrodo de platina de 15 ou 50 μm colocados cerca de 1 a 4 μm dentro do canal. Um eletrodo serviu como eletrodo de trabalho, posicionado no canal de separação, e o outro eletrodo como eletrodo de referência, posicionado no canal de referência. Essa configuração associado ao potenciostato eletricamente isolado permitiu que os sinais amperométricos fossem medidos sem qualquer mudança de potencial ou de interferência oriunda da alta tensão de separação aplicada. Objetivando avaliar a eficiência da metodologia proposta nessa tese, amostras de nitrito e peroxinitrito (espécies reativas de nitrogênio – ERN), tirosina, peróxido de hidrogênio (espécie reativa de oxigênio – ERO), ácido ascórbico, glutationa e cisteína foram injetadas no canal contendo o eletrodo de trabalho, enquanto que simultaneamente o tampão de ácido bórico contendo TTAB pH 11 foi injetado no canal de referência contendo o eletrodo de referência. A partir desta configuração, obteve-se uma significativa diminuição no nível de ruído (cerca de 0,94 pA) e uma relativa melhora na resolução ratificadas pelos eletroferogramas, se comparado com a configuração que utiliza canal único. Os limites de detecção (LOD) para as espécies químicas supracitados foram de 0,58 μM, 0,14 μM, 0,75 μM, 0,21 μM, 0,82 μM, não foi obtida para a cisteína, e 1,63 μM, respectivamente. A eficiência também pode ser vista através das análises de nitrito realizadas em amostras de perfusato de sangue de ovelhas e ratos, onde foram detectados uma concentração de 68,05 μM e 22,04 μM, respectivamente, através da metodologia proposta. Foi proposto também nessa tese, a microfabricação e avaliação de um microssistema eletroforético de PMMA com configuração de canal único acoplado a uma base feita do mesmo material para fixar o microchip, com detecção eletroquímica usando eletrodo de pasta de carbono. O objetivo da construção da base foi obter, através da fixação, reprodutibilidade de eventos. E a microfabricação do MSE de PMMA objetivou a viabilidade do seu uso em análises tendo como perspectiva o baixo custo por unidade confeccionada devido ao uso de laser de CO2 para a microfabricação, o qual possui um valor agregado consideravelmente menor, se comparado com os processos fotolitográficos. A avaliação desse sistema foi feita através das análises de padrões de serotonina e acetaminofeno, onde comprovou-se que a microfabricação desse sistema apresentou boa reprodutibilidade e repetitividade de eventos, tornando-se viável o seu processamento.