This thesis presents the design of multifunctional structures through the optimal placement of nanomaterial additives. Varying the concentration of Carbon Nanotubes (CNTs) in a polymer matrix affects its local effective properties, including mechanical stiffness, electrical conductivity, and piezoresistivity. These local properties in turn drive global multifunctional performance objectives. A topology optimization algorithm determines the optimal distribution of CNTs within an epoxy matrix in an effort to design a set of structures that are capable of performing some combination of mechanical, electrical, or peizoresistive functions. A Pareto-Based Restart Method is introduced and may be used within a multi-start gradient based optimization to obtain well defined multiobjective Pareto Fronts. A linear design variable filter is used to limit the influence of checkerboarding. The algorithm is presented and applied to the design of beam cross-sections and 2D plane stress structures. It is shown that tailoring the location of even a small amount of CNT (as low as 2 percent and as high as 10 percent, by volume) can have significant impact on stiffness, electrical conductivity, and strain-sensing performance. Stiffness is maximized by placing high concentrations of CNT in locations that either maximize the bending rigidity or minimize stress concentrations. Electrical conductivity is maximized by the formation of highly conductive paths between electrodes. Strain-sensing is maximized via location of percolation volume fractions of CNTs in high strain areas, manipulation of the strain field to increase the strain magnitude in these areas, and by avoiding negative contributions of piezoresistivity from areas with differing net signed strains. It is shown that the location of the electrodes can affect sensing performance. A surrogate model for simultaneous optimization of electrode and topology is introduced and used to optimize a 2D plane stress structure. This results in a significant increase in sensing performance when compared to the fixed-electrode topology optimization. / Ph. D. / This dissertation presents a method that allows for the best placement of a limited amount of filler material within a base matrix material to form an optimal composite structure. Adding filler material, in this case Carbon Nanotubes, can change the effective behavior of the composite structure, enhancing the capabilities of the base matrix material by adding structural stiffness, electrical conductivity, and even the ability for the structure to measure its own strains. The degree to which these changes occur is dependent on the amount of filler material present in any given subsection of the structure. The method then is focused on determining how much of the filler to place in different subsections of the structure to maximize several measures of performance. These measures pertain to structural performance, electrical conductivity, and the structure’s ability to sense strains. Steps are taken within the method to remove non-physical designs and also to find the overall best design, called the global minima. The method is applied to several test structures of varying complexity, and it is shown that the optimization method can heavily influence performance by tailoring the filler material distribution. Further electrical and sensing performance gains can be obtained by properly selecting where the electrodes are located on the structure. This is demonstrated by including electrode placement in the design method along with the filler distribution.

Biomedical devices play a crucial role in the healthcare system, enabling more effective treatments, less invasive procedures, and more precise diagnoses. Due to these compelling reasons, development of new biomedical devices and biomaterials have always been in high demand. Exploring and refining fabrication methods are essential to the development of new biomedical devices. Some of the common fabrication methods include microfabrication methods (photolithography and soft lithography), 3D printing (additive manufacturing), laser machining, thermal drawing, and electrospinning. The choice of fabrication methods heavily depends on the materials, geometry, and functionalities of biomedical devices. Currently, the thermal drawing process has proven to be an excellent scalable fabrication platform for neural interface, tissue engineering, tumor/cancer treatment, soft robotics, and smart textiles. This Ph.D. dissertation summarizes my research on the fabrication and validation of thermally drawn multifunctional polymer fiber probes for modern biomedical applications, primarily in the fields of neural interfaces and tumor treatments. Understanding the neural basis of behavior requires monitoring and manipulating combinations of physiological elements and their interactions in behaving animals. Utilizing the thermal drawing process, we developed T-DOpE (Tapered Drug delivery, Optical stimulation, and Electrophysiology) probes and Tetro-DOpE (Tetrode-like Drug delivery, Optical stimulation, and Electrophysiology) probes that can simultaneously record and manipulate neural activity in behaving rodents. Taking advantage of the triple-functionality, we monitored local field potential (LFP) while manipulating cannabinoid receptors (CB1R; microfluidic agonist delivery) and CA1 neuronal activity using optogenetics. Focal infusion of CB1R agonist downregulated theta and sharp wave-ripple oscillations (SPW-Rs). Furthermore, we found that CB1R activation reduces sharp wave-ripples by impairing the innate SPW-R-generating ability of the CA1 circuit. Microscale electroporation devices are mostly restricted to in vitro experiments (i.e., microchannel and microcapillary). We developed a flexible microscale electroporation fiber probe through a thermal drawing process and femtosecond laser micromachining techniques. The novel fiber microprobes enable microscale electroporation and arbitrarily select the cell groups of interest to electroporate. Successful reversible and irreversible microscale electroporation was observed in a 3D collagen scaffold (seeded with U251 human glioma cells) using fluorescent staining. Leveraging the scalable thermal drawing process, we envision a wide distribution of multifunctional polymer fiber probes in research facilities and hospitals. Along with the fiber probes presented in this dissertation, additional insight and future perspective on thermally drawn biomedical devices are discussed. / Doctor of Philosophy / The thermal drawing process is a versatile and scalable platform for fabricating functional fiber technology. The process was formerly adapted from fabrication method for silica optical fibers, widely used in telecommunication (e.g., telephone, internet, cable TV, etc.). To name some functionalities of these fibers, they can move, hear, sense touch, change colors, harvest and store energy, record and manipulate brain activity, and ablate tumors. As imagined, these functionalities are derived from the unique geometry and functional materials embedded along the fiber. Therefore, developing the fiber design tailored to a specific application is a critical step to making a successful fiber product. In this dissertation, I will present my work on biomedical devices fabricated with the thermal drawing process and their application in neuroscience and tumor/cancer treatment. Utilizing the thermal drawing process, we developed neural interfaces that can be implanted into the deep brain and record and simultaneously manipulate the neural activity. These neural interfaces (Chapter 2,3; T-DOpE and Tetro-DOpE probes, respectively) are able to record both local field potentials (LFP; activity of thousands or more neurons) and single action potentials (single on/off signal from individual neurons nearby). By manipulating the gene expression, we can control the activity of neurons with specific light (λ= 470nm; blue light) exposure. We implemented optical waveguide in our probes to guide light from a laser source to the tip of the probe and manipulate the neural activity. Furthermore, we fabricated micro-channels within the device to enable focal drug delivery at the tip of the device. Using the T-DOpE probe, we studied the effect of local synthetic cannabinoid injection in the hippocampus. We found that the local injection of the drug in hippocampus CA1 makes neurons incapable of generating sharp wave-ripples (a neural signal associated with memory). Electroporation is a biophysical phenomenon where short high electric field pulses introduce nanoscale defects in cell membrane. These defects can cause unstable cellular homeostasis and eventually leads to cell death. Due to reduced treatment time, no heat effect, and tissue selectivity, electroporation has been used in clinical trials for cancer treatments. Using the thermal drawing process and laser micromachining techniques, we developed a flexible microscale electroporation fiber probe capable of ablating tumor cells. Due to the low-cost and scalability of thermal drawing process, we envision the use of thermally drawn functional fiber technology in biomedical fields. In this dissertation, I also address some challenges and future directions of thermally drawn functional fibers in biomedical fields.

During the last decades, the continuing need for faster and smaller sensors has indeed triggered the rapid growth of more sophisticated technologies. This has led to the development of new optical-based sensors, able to detect and measure different phenomena using light. Furthermore, material processing technologies and micro fabrication methods have exponentially advanced, allowing engineers and scientists to develop new and more complex sensors on optical fibers platforms; specifically attractive for life science and biomedical research. All these substantial developments have brought biosensors to a point where multifunctionality is needed, this has led to envision the "Lab-on-Fiber" concept. Which promotes the integration of different sensing components into a single platform, an optical fiber. In this work, an integrated system with non-conventional polymer optical fibers and their further surface modification has been developed. With these different approaches, electrodes, hollow channels and plasmonic nanostructures can be incorporated into a single optical fiber-based sensor, allowing for both electrical and optical sensing with the capabilities of tuning and signal enhancement thanks to the metallic nanostructures. Different fiber substrates can be designed and modified in order to satisfy multiple requirements for a wide variety of applications. / MS / Silica optical fibers have been used since the 1960’s to guide optical signals, such as light, with low losses through long distances; making them an attractive platform to use in large communication systems. However, over the past couple of decades researchers have been trying to implement these low-loss platforms in sensing devices for many different fields, such as environmental and structural monitoring, and chemical and biomedical research. Unfortunately, their high brittleness has prompted researchers to introduce different materials in the same technology, leveraging the development of multimaterial non-conventional fibers. Where different polymers and even metals have replaced silica as the structural material, making these fibers more cost-affordable, flexible, and allow for multi-sensing capabilities of both electrical and optical signals. Although these multimaterial fibers are able to transmit light, they need to be functionalized or modified in order for them to be able to sense different phenomena occurring in their surrounding media. This can be achieved by integrating small particles or structures onto the fibers end-faces, these small structures are known as plasmonic nanostructures. When light (electromagnetic radiation) travels through a fiber and interacts with the free (conduction) electrons of a metallic nanostructure, it leads to a coupling that results in collective oscillations, which produce strong enhancement of the local electromagnetic fields surrounding the nanostructures. The latter can be easily detected with the help of an optical spectrum analyzer that iv stores the transmitted light as a function of the transmitted wavelength. Noble metals like gold and silver produce unprecedented electromagnetic field enhancements and are also biocompatible, making them very attractive in biosensing applications. In this research metallic plasmonic nanostructures were deposited on the end face of multimaterial polymer fibers to enhance the optical properties and potentially the electrical properties as well, creating new sensing devices. The enhancement produced by these structures was studied with both experimental measurements and theoretical simulations. The results demonstrate that the nanostructures investigated in this work can indeed enhance the optical properties of the used polymer fibers, enabling them to work as sensing probes for a many different applications, especially biosensing research.

Graphene nanoplatelets have been introduced into the interphase between electrically insulating glass fibre and polymer matrix to functionalize the traditional composite. Owing to the distribution of network structure of GNPs, the interphase can transfer the signals about various internal change of material. Consequently, due to the novel bio-inspired overlapping structure, our GNPs-glass fibre shows a unique opportunity as a micro-scale multifunctional sensor. The following conclusions can be drawn from present research: • We prepared GNPs solution via a scalable and highly effective liquid-phase exfoliation method. This method produces high-quality, unoxidized graphene flakes from flake graphite. We control the thickness and size of GNPs by varying the centrifugation rate. • A simple fibre oriented capillary flow which can suppress ‘coffee ring’ effect to deposit GNPs onto the curved glass fibre surface. The GNPs form continuous fish scales like overlapping structure. • The electrical conductivity of our GNPs-glass fibre shows semiconductive property. The electrical resistance value scattering and the advancing contact angle value scattering indicate a uniform deposit structure. The uniform overlapping structure is a key factor for higher electrical conductivity compared with our previous work with CNTs. • The contact angles of our GNPs-glass fibre with water indicate that the GNPs are almost unoxidized, so the inert GNPs coating decreases the interfacial shears strength. • A micro scale GNPs-glass fibre sensor for gas sensing is achieved by deposit GNPs onto glass fibre surface. This sensor can be used to detect solvents vapours, such as water, ethanol and acetone. All these vapours work as electron acceptor when reacting with GNPs. The acetone shows the highest sensitivity (45000%) compared with water and ethanol. • The doping-dedoping of GNPs-glass fibres during adsorption-desorption cycles of acetone result in the efficient “break-junction” (GNPs lost electron carrier concentration) mechanism, which provides the possibility to fabricate the electrochemical “switch” in a simple and unique way. • The resistance of our GNPs-glass fibre shows exponential relationship with RH. This is attributed to two points. Firstly, the water vapours show similar exponential adsorption on carbon surface; secondly, the bandgap of GNPs increases with the increase of adsorbed water vapour concentration. • Due to the weak van der Waals interaction when water molecules are adsorbed on GNPs surface, our GNPs-glass fibre shows extreme fast response and recovery time with RH. It is potential for our GNPs-glass fibre being used to monitor the breath frequency. • Utilizing the negative temperature coefficient of GNPs, our GNPs-glass fibre can be used as temperature sensor with a sensing region of -150 to 30 °C. • Through the observed abnormal resistance change at a temperature of about – 18 °C, we discovered a phase change of the trance confined water in graphene layers. Based on the resistance change, we can study the interaction of water and carbon nanoparticles. • The bio-inspired novel overlapped multilayer structure of GNPs coating shows structural colours. Even more, our GNPs-glass fibre can be used to monitor the loading force in the interphase when it is embedded into epoxy resin. • Our GNPs-glass fibre shows an excellent piezoresistive property, the single GNPs-glass fibre shows a larger gauge factor than the commercial strains sensor. • The semiconductive interphase was formed when the GNPs-glass fibre was embedded in polymer matrix. This semiconductive interphase is very sensitive to the deformation of material, therefore, an in-situ strain sensor was manufactured to real-time monitor the microcracks in a composite instead of external sensors. The area of resistance ‘jump’ increase can be seen as the feature area for damage’s early warning. • Monitoring the resistance variation of the single fibre composite was conducted under cyclic loading with progressively increasing the strain peaks in order to further investigate the response of in-situ sensor to the interphase damage process. The deviation of resistance/strain when the stress is larger than 2 % highlights the accumulation of damage, which gives insight into the mechanism of resistance change.

Santiago is the 7th largest major city of Latin America with almost 8 million inhabitants and is situated in a fairly closed watershed, surrounded on the eastern side by the high Andean mountain chain with altitudes of 5,000 m. From the Andean mountains, the Mapocho River and a set of large and small streams transport -often torrentially- water and sediment. In thirty years, Santiago has increased its size two fold, replacing previous agricultural lands, native forests and shrubs with urban land uses, and occupying rivers beds and streams. These land use and cover changes have had dramatic environmental consequences. The mentioned urban dynamic has produced a city in constant collision with the natural system. This structural disarticulation produces many environmental problems such as an increase in city’s surface and air temperatures, an accelerated disappearance of vegetation, a major interruption in wind, sediment and water flows, and finally, increasing people’s exposure to environmental hazards. Since streams, canals and rivers are structural components of Santiago’s landscape, they can function as key links between the urban-social and natural system and provide multiple ecosystem services, helping to reduce environmental problems and ensure long-term urban sustainability. Traditionally, the analysis of river and streamsides has been focused on rural and natural landscapes as well as on environmental protection and nature conservation. Nowadays, there is an increasing interest and necessity to understand the environmental status, functions and possibilities of riparian zones in urban environments in order to delineate and plan greenways, which provide social and ecological benefits. Green infrastructure such as urban greenways is a key component of sustainable cities. Few studies have been conducted to evaluate the socio-ecological status of urban riparian zones and even fewer to assess these areas in terms of their potential as multifunctional greenways. New efforts should be conducted to develop analytical application-oriented frameworks in the green infrastructure field. This research elaborates and proposes a transferable conceptual-methodological framework for evaluating the potential for multifunctional riparian greenway development. An analytical application-oriented framework to assess the potential for multifunctional green infrastructure development is proposed by articulating and improving three analyses hitherto used separately: multicriteria, least cost path and opportunities-challenges. The Mapocho River was selected for the application and testing of the proposed conceptual-methodological framework to contribute to multifunctional green infrastructure planning in Santiago as a city representative of the structure and processes of megacities in Latin America. First, the main ecological and social characteristics of the Mapocho’s riparian zone are analyzed, making a synthesis of the socio-ecological status. Second, the suitability to provide multiple ecosystem services of the riparian zone is spatially explicitly modelled, first separately, as mono-functional suitability, and then, integrated into a multifunctional suitability evaluation. Third, the opportunities and challenges perceived by government actors are identified and analyzed as well as those derived from an institutional and regulatory analysis. Finally, the assessment phase concludes with a discussion on the main potential for the development of a greenway, resulting from the synthesis and integration of the most relevant findings of the suitability and opportunities analysis The socio-ecological status of the riparian zones is characterized by being highly altered in ecological terms, diverse in social terms, and highly used by the metropolitan transport infrastructure with a concentration of green areas in a few municipalities. This means that the riparian zone provides limited physical support for important social and ecological functions characteristic of these zones in urban environments: habitat, aesthetic, cooling, transport route and flood mitigation. The results reveal a significant east-west gradient in the socio-ecological status of riparian zone, which gradually decreases from east to west. The riparian zone of the Mapocho River in Santiago has good suitability as a wind corridor, providing a cooling effect and to mitigate flood hazards. The main challenges for the development of a multifunctional urban greenway in the Mapocho River corresponds to low levels of inter-jurisdictional and inter-sectoral coordination and cooperation, maintenance costs and the existence of urban highways in the zone. On the contrary, the main opportunities are the existence of important sectors of vacant land, increased political and social importance of urban green areas and the existence of a set of consolidated riparian parks. In synthesis, the assessment developed in the Mapocho River identifies the most important aspects to be considered and the greatest potentialities to capitalize in planning a multifunctional greenway along the Mapocho River. This is key when thinking about a possible master plan for the Mapocho River that returns the river to the city and values it as an axis for urban integration. The development of a multifunctional greenway in Santiago can considerably contribute to the social and ecological connectivity and thereby mitigate the socio-ecological segregation and disconnection characteristic of cities in the region. It may also contribute significantly to reconcile urban growth with ecological health and people’s quality of life, maintaining functions and key ecosystem services and mitigating the negative effects of urbanization.

A utilização de nanopartículas magnéticas em biomedicina e biotecnologia vem recebendo elevado destaque nos últimos anos, graças à versatilidade de aplicações como reparo de tecidos, diagnósticos, ressonância magnética por imagem, tratamento contra o câncer, separação celular, transporte controlado de drogas, entre outras. Atualmente, as nanopartículas com potencialidade de aplicação em biomedicina se restringem aos óxidos magnéticos de ferro, os quais apresentam comportamento superparamagnético a temperatura ambiente e magnetização da ordem de 300 emu/cm3. Entretanto, há necessidade inerente da funcionalização da superfície para possibilitar aplicações biomédicas tornando as nanopartículas biocompatíveis e/ou biosseletivas. Essa funcionalização adicional é obtida geralmente introduzindo camadas de materiais diamagnético e/ou paramagnéticos na superfície das NP, as quais baixam a eficiência das propriedades magnéticas exigindo o desenvolvimento de núcleos com elevado valor de magnetização de saturação. Desta forma, nesse trabalho foram sintetizadas nanopartículas magnéticas metálicas de FePt recobertas com óxido de ferro obtidas via processo poliol modificado combinado com a metodologia de crescimento mediado por sementes. Os núcleos magnéticos como-sintetizados foram recobertos com uma camada de sílica, seguido pelo recozimento em atmosfera redutora para elevar o valor da magnetização de saturação. Em seguida, sobre a superfície de sílica foram ancoradas moléculas luminescentes de rodamina B com o auxílio de moléculas de APTES atuando como grupo sililante e as NP resultantes foram novamente recobertas com uma fina camada de sílica. Os resultados permitem concluir que foi obtido um sistema bifuncional combinando em uma única nanopartícula a possibilidade de sensoriamento óptico e magnético, além de possuir sua magnetização de saturação intensificada cerca de 10 vezes em relação aos óxidos metálicos (64 emu/g), manter o caráter superparamagnético e possuir superfície biocompatível com possibilidades de funcionalizações adicionais, com grande potencial para aplicações em biomedicina. / In recent years, the magnetic nanoparticles uses in many biomedical and biotechnological areas have received great attention due to their several applications possibilities such as: tissue repair, diagnostics, magnetic resonance imaging, cancer treatment, cell separation, and controlled drug delivery, among others. Today, the potential magnetic nanoparticles applications are limited to magnetic iron oxides uses, which exhibit superparamagnetic behavior at room temperature and low saturation magnetization around 300 emu/cm3. However, for biomedical applications, the nanoparticle surface must be properly functionalized in order to confer biocompatibility and biosselectivity. These additional functionalizations are generally obtained by paramagnetic and/or diamagnetic materials incorporations onto the nanoparticle surface leading a dramatic decreasing in the already low saturation magnetization. In this context, the development of new magnetic nuclei with high magnetizations values is required. Thus, in this work iron oxide-coated metallic FePt magnetic nanoparticles were synthesized by using the modified polyol process combined with the seed mediated growth method. The magnetic as-synthesized nuclei were coated with a thin silica shell followed by thermal annealing under reducing atmosphere in order to increase the saturations magnetization of this material. After that, onto the silica-coated magnetic nanoparticles surface luminescent dye Rhodamine B molecules were supported using the APTES as intermediate sililant molecules. Then, the functionalized nanoparticles were coated again with an outer layer. In conclusion, according to the obtained results, a bifunctional system combining the optical and magnetic sensing in the same nanoparticle was reported. The obtained nanoparticles present superparamagnetic behavior and high saturation magnetization around 10 times higher (~64 emu/g) compared with the iron oxide nanoparticles synthesized at the same conditions. In addition, the luminomagnetic nanoparticle surface is biocompatible allowing additional future functionalizations with high potential to biomedical applications.

Les polyélectrolytes sont des polymères chargés, solubles dans l'eau, omniprésents dans les nature et capables d’interagir avec de nombreux composants cellulaires. Leur utilisation dans des essais cliniques est actuellement limitée par le manque de données fiables sur les relations entre leurs structures et leurs biopropriétés. Ce projet s'inscrit dans un programme plus vaste visant à obtenir une bibliothèque de polyélectrolytes multifonctionnalisés bien caractérisés pour le criblage de biopropriétés. Dans ce cadre, nous avons cherché à synthétiser des chaînes macromoléculaires contenant des unités maloniques C(COOH)2 situées à différentes positions le long du squelette du polymère. Ces unités peuvent être utilisées comme points de départ pour introduire plusieurs autres groupes fonctionnels en utilisant de nombreuses réactions de la chimie organique, conduisant à un grand nombre de structures à partir d'un squelette commun, y compris des copolymères. Cette thèse est schématiquement divisée en quatre parties : (a) une présentation bibliographique des relations existant entre structures et propriétés pour des polymères multifonctionnalisés, suivie d'une analyse plus spécifique de l'importance du positionnement d’esters carboxyliques le long d’une chaîne carbonée, (b) une description des efforts expérimentaux menés pour obtenir les poly(triméthylène-1,1-dicarboxylate)s, des intermédiaires clés dans la synthèse des polymères décrits dans les chapitres suivants, (c) une description de l'hydrolyse du précurseur ci-dessus, donnant l'acide poly(triméthylène-1,1-dicarboxylique), ainsi que des propriétés et de la réactivité de ce polyacide, (d) un rapport détaillé sur la synthèse de l’acide poly(triméthylène carboxylique) par décarboxylation quantitative du polyacide ci-dessus, ainsi que sur les propriétés et réactivité de ce polyacide. Dans les deux dernières sections, un accent particulier est mis sur la portée et les limites de diverses procédures de post-fonctionnalisation lorsque l'on tente d'obtenir une bibliothèque de polymères fonctionnels à partir de précurseurs polycarboxyliques / Polyelectrolytes are water-soluble charged polymers that are ubiquitous in life science and capable of interacting with many cellular constituents. Their use in clinical trials is currently limited by a lack of reliable data on the relationships linking their structures to bioproperties. This project is part of a larger program aimed at obtaining a library of well-characterized multifunctionalized polyelectrolytes for the screening of bioproperties. In this framework, we aimed at synthesizing macromolecular chains containing malonic units C(COOH)2 located at various positions alongside the polymer backbone. These units can be used as starting points to introduce several other functional groups using many reactions from organic chemistry, leading to a great number of structures from a common skeleton, including copolymers. This thesis is schematically divided into four parts: (a) a bibliographical presentation of the relationships existing between structures and properties for multifunctional polymers, followed by a more specific analysis on the importance of carboxylic esters positioning alongside a carbon chain backbone, (b) a description of experimental efforts aimed at obtaining poly(trimethylene-1,1-dicarboxylate)s, key intermediates in the synthesis of a large family of polymers described in the next chapters, (c) a depiction of the hydrolysis of the above precursor, yielding poly(trimethylene-1,1-dicarboxylic acid), as well as of the properties and reactivity of this polyacid, (d) a detailed report on the synthesis of poly(trimethylenecarboxylic acid) via the quantitative decarboxylation of the above polyacid, as well as of the properties and reactivity of this polyacid. A special focus is made in the last two sections on the scope and limitations of various post-functionalizing procedures when attempting to obtain a large library of functional polymers from polycarboxylic precursors

Le développement des nanoparticules fluorescentes, appelées quantum dots (QDs) est devenu l'un des domaines les plus prometteurs de la science des matériaux. Dans cette étude une procédure de synthèse de QDs a été mise au point, comprenant la synthèse de noyaux ultra-minces de CdSe, la purification de noyau haute performance, le revêtement central avec une coquille épitaxiale en ZnS. Cette approche a permis d’obtenir des QDs d’une taille de 3,7 nm possédant un rendement quantique supérieur à 70%. Les QDs développés ont été utilisés pour concevoir des conjugués de QDs compacts avec les nouveaux dérivés d'acridine, ayant une affinité élevée pour le G-quadruplex des télomères, ainsi que leur effet inhibiteur sur la télomérase, une cible importante du traitement du cancer. Les résultats de cette étude ouvrent la voie à l'ingénierie de nanosondes multifonctionnelles possédant une meilleure pénétration intracellulaire, une plus forte brillance et une stabilité colloïdale plus importante. / Development of the fluorescent nanoparticles referred to as quantum dots (QDs) has become one of the most promising areas of materials sciences. In this study, a procedure of synthesis of QDs, which includes the synthesis of ultrasmall CdSe cores, high-performance purification, core coating with an epitaxial ZnS shell has been developed. This approach has allowed obtaining 3.7-nm QDs with a quantum yield exceeding 70%. The QDs have been used: to engineer compact conjugates of QDs with the novel acridine derivatives, which have a high affinity for the telomere G-quadruplex; to demonstrate their inhibitory effect on telomerase, an important target of anticancer therapy; and to accelerate transmembrane penetration of ultrasmall QDs into cancer cells while retaining a high brightness and colloidal stability. The results of this study pave the way to the engineering of multifunctional nanoprobes with improved intracellular penetration, brightness, and colloidal stability.

This master thesis from Industrial Design Engineering, Product Design, at Luleå University ofTechnology, has been formulated and assigned by Polardörren AB. Today’s manufacturing companiesoften display their products by using sample products in physical stores. Polardörren AB is a doormanufacturing company located in northern Sweden and have a wish to be experienced as a creativeand flexible company. Competitors to Polardörren AB have started using digital software to let theircustomers experiment with the composition of their products. This provides huge possibilities inrepresentation, however, digital is not always better. Digital representations mean a complete lackof feeling for material or quality. Ideally you would be able to combine the freedom of the digitalworld with the feeling of the physical world, and this is where our model fits in perfectly. We havedeveloped a prototype that, with the use of modularity, can represent many of Polardörren AB’sproducts in an effective and compressed way. By using the same type of material as the companyuse in their regular products, we present the user with a similar feeling as from the real products.Neodymium magnets lets a consumer, in an easy way, create and explore custom-made designsbased on their personal needs and wishes. By involving the end-user in the design process, webelieve that the number of purchases of the company’s products, and the general opinion towardsthe company, will increase. This could lead to increased revenue for both resellers and manufacturer.During the development process of this prototype, areas such as industrial design, semiotics, userexperience and usability has been explored. Methods used in this project ranges from brainstormingand brainwriting to computer modelling and CNC-milling. If this prototype would replace one ofthe existing product samples at the reseller today, the cost for representation would be estimated togo down to one third of the cost today. By using material that the company already have in theirproduction today, we make a minimal impact on the environment by preventing excess deliveriesfrom new distributers.

Cette thèse de doctorat aborde de nouvelles conceptions de films à base de résines d’ester de cyanate (CER) en présence de liquides ioniques (LIs) en tant qu'agents multifonctionnels : catalyseurs, agents de modification réactifs, renforts ou agents porogènes. Les liquides ioniques de structures et de concentrations variables accélèrent de manière significative la polycyclotrimérisation du dicyanate d’ester de bisphenol E, en l'absence de tout solvant organique supplémentaire ou additif. Les réseaux de polycyanurates resultants dopés avec des liquides ioniques aprotiques peuvent constituer des matériaux prometteurs pour la production de structures photosensibles. De tels systèmes nanocomposites permettent la séparation, larécupération et le recyclage aisés des LIs par simple extraction, ce qui permet finalement l'obtention de films nanoporeux thermostables. Les caractéristiques de la porosité de ces matériaux dépendent de la concentration des LIs dans les précurseurs CERs. Les LIs protoniques contenant des groupements fonctionnels >NH et -OH, indépendamment de leurmasse molaire, de la structure chimique du cation et de l'anion, sont incorporés chimiquement dans le réseau polycyanurate. Ainsi, les matériaux hybrides obtenus avec des fragments de liquides ioniques pourraient fournir d’excellents candidats pour des recherches futures sur les ionomères et les nanocomposites. / This PhD thesis addresses new designs of cyanate ester resin (CER) films in the presence of ionic liquids as multifunctional agents: catalysts, reactive modifiers, fillers or porogens. It should be emphasized that ionic liquids (ILs) of varying structures and concentrations significantly accelerate the polycyclotrimerization of dicyanate ester of bisphenol E, in the absence of any additional organic solvent or additive. The resulting polycyanurate networks doped with aprotic ionic liquids can be promising materials for producing photosensitive structures. Such nanocomposite systems allow for easier separation, recovery, and recycling of ILs by mere extraction, which eventually affords thermally stable nanoporous films. The porosity features of these materials depend on the concentration of ILs in the CER precursors.Protic ILs containing functional >NH and -OH groups, regardless of molar mass, chemical structure of cation and anion, chemically incorporate into the polycyanurate network, thus the resulting hybrid materials with fragments of ionic liquids could provide excellent candidates for future research in ionomers and nanocomposites.