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Bone repair is modulated by different stimuli. There is evidence that the Transforming Growth Factor-beta (TGF-β) super-family of cytokines have significant effects on bone structure by regulating the replication and differentiation of chondrocytes, osteoblasts and osteoclasts. There is also significant evidence that interactions with extracellular matrix molecules also influence cell behaviour. This study aimed at determining the role of the TGF-βs, Collagen type I, Fibronectin and Laminin in bone cell behaviour. To do this MG63 bone cells were used to examine cell adhesion and alignment to different micro-contact printed ECM protein patterns of different widths. The study also aimed at examining how TGF-β1, 2 and 3 and their solvent and carrier (HCl and BSA, respectively) effected cell surface interactions, cell morphology, cell proliferation and integrin expression. Finally, this study also aimed at examining how the TGF-βs and their solvent and carrier influenced wound closure in an in vitro wound closure model and how TGF-βs influence ECM secretion and integrin expression. 5, 10, 25, 50 and 100μm wide repeat gratings of Collagen type I, Fibronectin and Laminin patterns were stamp patterned onto glass slides and plated with MG63 cells at 50,000 cells per coverslip. Cells on the fibronectin pattern attached and elongated soon after seeding, but did not adhere readily to collagen and laminin and appeared more rounded until 18hrs after seeding. Cells aligned significantly well on the 50μm and 100μm wide fibronectin patterned coverslips with mean angles of alignment ~7.87° ± 3.06SD and 6.45° ± 5.08SD, respectively, compared to those with smaller width (p<0.001). In comparison, cells aligned less readily to the other two ECM proteins, showing optimal alignments of 9.66° ± 4.18SD and 14.36° ± 1.57SD to the 50μm wide collagen and laminin patterns, respectively. Differences in cell length mirrored those of alignment, with cells acquiring the greatest length when showing the greatest degree of alignment. The results indicate that MG63 cells responded significantly better to 50 and 100μm wide fibronectin patterns compared to those with smaller width (p<0.001) indicating that the cells may attach mostly via fibronectin specific integrins. Cell surface attachment was examined via a trypsinisation assay in which the time taken to trypsinise cells from the surface provided a means of assessing the strength of attachment. The results indicated that treatment with the solvent (HCl), TGF-β1, 2 and 3 all decreased cell attachment, but this effect was significantly greater in the case of HCl and TGF-β3 (p<0.001). However, there were significant differences in trypsinisation rates between HCl and TGF-β3 (p<0.001). The wound healing response to the TGF-βs and their solvent/carrier was also investigated in 300μm ± 10-30μm SD wide model wounds induced in fully confluent monolayers of MG63 bone cells. The results indicated that TGF-β3 and HCl significantly enhance wound closure when compared against negative controls, TGF-β1 and TGF-β2 treatment (p<0.001). It was also found that TGF-β1 and TGF-β2 treatment significantly improved wound closure rate in comparison to the controls (p<0.001). Experiments were performed to determine if the HCl effects on wound closure were dose dependent. Cells were incubated with 20μM, 40μM, 80μM and 160μM concentrations of HCl prior to wounding and wound closure rates were recorded. Wound closure was dependent on HCl dose with the 80μM and 160μM concentrations inducing increases in wound closure rates that were both significantly greater than those induced by 20μM, 40μM and control treatments (p<0.001). However, there were significant differences in wound closure between the 80μM and 160μM treatment groups after 30hrs of treatment (p<0.001). The effect of different TGF-β isomers and their combinations on proliferation rate and cell length of human bone cells were also assessed. The results suggest that cell morphology changes were observed significantly more in cells treated with TGF-β(2+3) and TGF-β(1+3) (p<0.001). Any cell treated with TGF-β1, TGF-β(1+2) and TGF-β(1+2+3) showed significantly less elongation compared to the control and other TGF-β isomers. In terms of proliferation rate, TGF-β3 and TGF-β(2+3) increased cell numbers more than TGF-β1, TGF-β2 and other combinations. TGF-β1 and its combinations did not show significant proliferation and attachment compared to the control due to perhaps its inhibitory effect in contact with human bone cells. Immunostaining indicated that treatment with TGF-β3 significantly promoted the secretion of collagen type I and anti-human fibronectin in addition to integrin (α3 and β1) expression. Statistically TGF-β3 and their combinations showed significant differences in number of cells stained for collagen type I, anti-human fibronectin, α3 and β1 integrin. Any cell treated with TGF-β1 or any combination with TGF-β1 showed significantly lower cell number stained with the same proteins and integrins (p<0.001). Imaging with WSPR allowed observation of the focal contacts without the need for immunostaining. WSPR images revealed guided cells with high contrast band like structures at the border of cells distal to the edge of guidance cue to which they aligned and with less concentrically formed band like features across the cell body. It is believed that the high contrast features are associated with the formation of focal contacts on the edge of the cells distal to the edge of fibronectin patterns, which suggests that cell guidance is aided by a decrease in cell attachment along a guidance feature. The WSPR experiments also indicated that TGF-βs influenced the distribution of focal contacts. In the case of TGF-β1 treated cells the bright high contrast regions were intense but only arranged around the periphery of the cell. In TGF-β2 and TGF-β3 cells the bright contrast regions were weaker but again mostly localised around the periphery. These findings supported the earlier trypsinisation results.

Afin de réaliser des dispositifs en polymère à forte valeur ajoutée, l'industrie de la plasturgie s'intéresse depuis quelques années à la convergence possible entre les microtechnologies et les méthodes industrielles de mise en oeuvre des polymères (le thermoformage et la thermo-injection). Dans ce contexte, l'objectif de cette thèse est de démontrer l'intérêt d'une approche à base de microtamponnage pour l'intégration de capteurs à base métallique dans des circuits microfluidiques en thermoplastique réalisés par thermoformage. Pour ces matériaux, cette approche apparait plus pertinente en terme de production de masse qu'une approche de photolithographie classique. Nous avons choisi de démontrer ce concept en étudiant l'intégration d'un capteur de pH et d'un capteur de température dans un système microfluidique en copolymère d'oléfine cyclique (COC) réalisé par thermoformage. En effet, la mesure de ces paramètres physico-chimiques est extrêmement répandue dans différents domaines d'application allant de la chimie à la biologie et à la médecine. Pour le capteur de pH, nous avons développé une couche sensible au pH à base d'oxyde d'iridium (IrOx) électrodéposé sur or. L'influence de différents paramètres (solution d'électrodépôt, méthode d'électrodéposition, nature du substrat métallique et son mode de préparation) sur la réponse au pH de ces couches a été étudiée. Nous avons ainsi pu démonter qu'une approche par microtamponnage passive est adaptée à la préparation de capteurs de pH sur un substrat en COC/Au ayant une sensibilité de -72 mV/pH et une durée de vie de 1 an. Pour le capteur de température, la solution retenue est basée sur le principe d'une thermorésistance. Les capteurs ont été élaborés en utilisant une approche par microtamponnage actif avec croissance d'une couche de nickel (dont l'épaisseur varie entre 0,2 et 5 μm) par métallisation autocatalytique sur polyimide. La dérive des capteurs est actuellement trop importante pour une application pratique. Finalement, des résultats préliminaires d'intégration de ces capteurs dans un microsystème fluidique thermoformé sont présentés avec notamment une configuration originale de mesure différentielle du pH / The plastics industry has been interested for some years in the possible convergence between microtechnologies and conventional polymer manufacturing (hot embossing and injection molding). In this context, this thesis aims at demonstrating the potential of a process based on microcontact printing in order to integrate metal based sensors in thermoplastic microfluidic devices shaped by hot embossing. For the mass production of thermoplastic devices, this approach appears more relevant than conventional photolithography. We chose to demonstrate this concept by investigating the integration of both a pH sensor and a temperature sensor in a thermoformed Cyclo Olefin Copolymer (COC) microfluidic system. Indeed, the measurement of these physicochemical parameters are extremely widespread in different applicative areas ranging from chemistry tobiology and medicine. For the pH sensor, we developed a pH-sensitive layer based on electrodeposited iridium oxide (IrOx) on Au. The influence of various parameters (plating solution and method , nature of the metal substrate and its method of preparation) on the pH response of these layers was studied. We were able to demonstrate that microcontact printing based on a passive approach is suitable for the preparation of pH sensors on a COC substrate with a sensitivity of -72 mV/pH and a 1 year lifetime. As regards the temperature sensor, the solution was to design a thermistor. Sensors were implemented with an approach based on active microcontact printing followed by electroless deposition of nickel (thickness varies between 0,2 and 5 μm) on polyimide. The drift of these sensors is too large for practical application. Finally, preliminary results presenting the integrating of these sensors in a fluidic microsystem are reported using an original configuration based on differential measurement of pH

This thesis studies a scheme to fabricate small-scaled metal structures by electrochemical metal deposition and lift off. The key point is the use of self-assembled monolayers (SAMs) to control both interfacial charge transfer in electrodeposition and adhesion of the deposit to the substrate. Patterned SAMs exhibiting blocking and non-blocking areas are applied as templates in electrochemical deposition of Cu or Au. Thiol SAMs on Au substrates are used, namely alkane thiols and thiols combining an aliphatic chain with a biphenyl or biphenyl analogous pyridine-phenyl moieties. The patterning of SAMs is realised with microcontact printing (μCP) and electron beam lithography. Electrochemical deposition based on defects in the SAMs is optimised towards generating small nanostructures and depending on the system single or stepped potential procedures are applied. Generated metal structures are transferred to an insulator by lift off. Au microstructures (~10 μm) have been made with microcontact printing and transferred onto epoxy glue, which can potentially be used as microelectrodes in electroanalytical chemistry. Sub-100 nm Cu features and sub-40 nm Au features have been created with electron beam lithography respectively. Lift off process has successfully transferred Cu nanostructures onto epoxy glue with high precision. In contrast to the deposition mediated by defects, Cu deposition mediated by discharging Pd²⁺ coordinated to a pyridine terminated SAM directly through the SAM molecules has been explored as a new approach. This new approach has potential to decrease the size of the metal structure further and the preliminary results show possibility of sub-10 nm features. SAMs prepared with a newly synthesised molecule, 3-(4'-(methylthio)-[1,1'-biphenyl]-4-yl)propane-1-thiol, are characterised by STM, XPS and NEXAFS. The metal structures are investigated by SEM, AFM and STM.

Avec une limite de détection ultime pouvant atteindre le yoctogramme (1 yg = 10-24 g), les nanosystèmes électromécaniques (NEMS) employés comme capteurs gravimétriques présentent un fort potentiel pour la détection ultra-sensible et sans marquage de molécules biologiques. A l’heure actuelle, plusieurs défis restent cependant à relever avant de pouvoir envisager de manière réaliste leur utilisation comme outils de biodétection. Ces travaux de thèse adressent en particulier l’intégration du moyen de transduction et le développement de stratégies de biofonctionnalisation. En vue de répondre à la première problématique, l’intégration d’une couche piézoélectrique à base de Titano-Zirconate de Plomb (PZT) selon une approche de fabrication collective de réseaux de NEMS par voie descendante a été développée et caractérisée.Deux approches de biofonctionnalisation adaptées à une organisation de NEMS en réseaux,respectivement basées sur le dépôt localisé de matériel biologique par impression moléculaire et sur la structuration par photolithographie d’une couche bioréceptrice à base de polymères à empreintes moléculaires (MIP), ont ensuite été mises en oeuvre et ont permis de démontrer une première preuve de concept. Ces différentes contributions constituent un premier pas dans le développement des NEMS pour des applications de biodétection. / With an ultimate limit of detection down to the yoctogram regime (1 yg = 10-24 g),nanoelectromechanical systems (NEMS) resonators used as ultra-sensitive and label-free gravimetric sensors have a high potential for biodetection applications. To date, several challenges currently limit their wide spread use as viable biosensing tools. This PhD thesis addresses the issues related to the transducer integration and the biofunctionnalization. A Lead Zirconate Titatane (PZT)-based piezoelectric transducer has been implemented according to a top-down approach compatible with collective fabrication of NEMS arrays. Two biofunctionnalization strategies, suitable for a NEMS array organization and based on the localized deposition of biological material assisted by microcontact printing and the patterning of molecularly imprinted polymers (MIP) by photolithography, have also been investigated and first proof-of-concept biosensors were demonstrated. These various contributions have the potential to drive future advancements in the realm of NEMS as effective biosensing tools.

Tesis por compendio / [ES] El desarrollo científico y tecnológico de las últimas décadas ha dado lugar a sistemas sensores capaces de obtener, procesar y transmitir información sobre multitud de aspectos físicos y químicos, y utilizarla para mejorar aspectos clave de multitud de áreas de nuestra sociedad. Los sensores químicos son dispositivos compactos y miniaturizados capaces de ofrecer soluciones alternativas a las técnicas de análisis instrumental convencionales. En especial, los biosensores han adquirido gran relevancia por los avances que han supuesto para sectores estratégicos como el diagnóstico clínico, la industria alimentaria y el medio ambiente. Los biosensores ópticos se basan en interacciones entre la luz y la materia para transducir eventos de bioreconocimiento y presentan prestaciones importantes como la estabilidad, inmunidad a estímulos externos y versatilidad en el desarrollo de aproximaciones sin marcaje (label-free). Este último aspecto suele aprovechar fenómenos nanoscópicos y su desarrollo se encuentra muy ligado al progreso de la nanociencia y nanotecnología. Un aspecto clave en el biosensado sin marcaje consiste en descubrir y desarrollar nuevas estrategias de transducción. En este sentido, aunque se encuentren aun en una etapa temprana de desarrollo, los biosensores difractivos presentan un gran potencial en términos de simplicidad, miniaturización, y capacidad para minimizar señales no deseadas fruto de interacciones no específicas, entre otros aspectos. / [CA] El desenvolupament científic i tecnològic de les últimes dècades ha donat lloc a sistemes sensors capaços d'obtindre, processar i transmetre informació sobre multitud d'aspectes físics i químics, i utilizar-la per a millorar aspectes clau de multitud d'arees de la nostra societat. Els sensors químics són dispositius compactes i miniaturitzats capaços d'oferir solucions alternatives a les tècniques d'analisi instrumental convencionals. Especialment, els biosensors han adquirit gran rellevància pels avanços que han suposat per als sectors estratègics com el diagnòstic clínic, la industria alimentària i el medi ambient. Els biosensors òptics es basen en interaccions entre la llum i la matèria per a transduir esdeveniments de bioreconèixement i presenten prestacions importants com estabilitat, immunitat a estímuls externs i versatilitat en el desenvolupament d'aproximacions sense marcatge (label-free). Aquest últim aspecte sol aprofitat fenòmens nanoscòpics i el seu desenvolupament es troba molt lligat al progrés de la nanociència i nanotecnologia. Un aspecte clau en el biosensat sense marcatge consisteix a descobrir i desenvolupar noves estratègies de transducció. En aquest sentit, encara que es troben fins i tot en una etapa primerenca de desenvolupament, els biosensors difractius presenten un gran potencial en termes de simplicitat, miniaturització, i capacitat per a minimitzar senyals no desitjats fruit d'interaccions no específiques, entre altres aspectes. / [EN] The scientific and technological progress in recent decades has given rise to sensor systems capable of obtaining, processing, and transmitting information on a multitude of physical and chemical aspects and using it to improve key aspects of many areas of our society. Chemical sensors are compact, miniaturized devices capable of offering alternative solutions to conventional instrumental analysis techniques. In particular, biosensors have become highly relevant due to the progress they have brought to strategic sectors such as clinical diagnostics, the food industry, and the environment. Optical biosensors rely on interactions between light and matter to transduce biosensing events and provide important features such as stability, immunity to external stimuli, and versatility in the development of label-free approaches. This last aspect usually exploits nanoscopic phenomena and its development in closely linked to the progress in nanoscience and nanotechnology. A key aspect of label-free biosensing is the discovery and development of new transduction strategies. In this regard, although they are at an early stage of development, diffractive biosensors offer great potential in terms of simplicity, miniaturization, and the ability to minimize unwanted signals from non-specific interactions, among other aspects. / This work was financially supported by the Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033) co-funded by the European Union “ERDF A way of making Europe” (PID2019-110713RB-I00, TED2021-132584B-C21, PID2019-110877GB-I00), Ministerio de Economía y Competitividad (TEC2016-80385-P), Generalitat Valenciana (PROMETEO/2019/048 PROMETEO/2020/094, PROMETEO/2021/015, IDIFEDER/2021/046). A.J.D. ackowledges the FPI-UPV 2017 grant program. The authors acknowledge Instituto de Microelectrónica de Barcelona CNM-CSIC for the support in the fabrication of the measured chip samples on the Multiproject CNM-VLC silicon nitride technology platform. / Juste Dolz, AM. (2023). Biogratings: Diffractive Transducers for Biosensing in Photonic Platforms [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/194251 / Compendio

Grâce à leurs propriétés physiques/chimiques uniques, les nanoparticules colloïdales sont au cœur de nombreuses applications innovantes. Afin de faciliter leur caractérisation ou de les intégrer dans des dispositifs fonctionnels, il est nécessaire de les assembler de manière dirigée sur des surfaces solides. Dans ce contexte, l’objectif de cette thèse est de mieux comprendre et d’optimiser la technique de nanoxérographie, méthode d’assemblage dirigé où des nanoparticules sont piégées sur des motifs de charges électrostatiques. Après un premier travail consistant à améliorer le procédé de nanoxérographie, trois problématiques spécifiques ont été adressées : (i) l’assemblage de particules micrométriques. Le couplage de simulations numériques et de manipulations expérimentales a permis d’identifier les paramètres clés de l’assemblage de telles particules colloïdales et d’élargir (facteur 100) la gamme de tailles de particules assemblables par nanoxérographie. (ii) l’analyse de l’assemblage multicouche. Par le biais de nanoparticules modèles luminescentes et par la mise en place d’un nouveau protocole d’assemblage, les critères clés génériques pour l’assemblage 3D de colloïdes par nanoxérographie ont été dégagés. (ii) l’assemblage dirigé de nanogels sensibles à un stimulus environnemental extérieur. L’utilisation d’un protocole d’assemblage optimisé a permis d’élaborer des assemblages de nanogels interactifs avec leur environnement et du faire du tri sélectif de ces nanoparticules sur une même surface. / Owing to their unique physico-chemical properties, colloidal nanoparticles are building blocks for the creation of plentiful innovative devices. In order to make easier their characterization and to incorporate them into functional nano-devices, it is necessary to perfectly control their directed assemblies onto solid surfaces. In this context, this thesis’ purpose is to simultaneously better understand and optimize the nanoxerography method, which allows electrostatic and selective directing assemblies of nanoparticles onto charged patterns. After an optimization of the nanoxerography process, three specific problematics have been addressed: (1) micron-sized particles assembly. The combined use of numerical simulations and experiments enabled to unveil the key parameters involved in micron-sized particles assembly and to expend the particle size range foreseeable for an assembly by nanoxerography (factor 100). (2) the 3D assembly analysis. The influence of diverse parameters on the 3D assembly of luminescent model nanoparticles was quantified by using a new assembly protocol. The results gave the generic key criterions for the 3D assembly of colloids by nanoxerography. (3) directed assembly of nanogels sensitive to an external environmental stimulus. The use of an optimized protocol allowed elaborating nanogels assemblies interactive with their environment and to sort these nanoparticles onto the same surface.

The field of micro total analysis systems (μTAS) aims at developments toward miniaturized and fully integrated lab-on-a-chip systems for applications, such as drug screening, drug delivery, cellular assays, protein analysis, genomic analysis and handheld point-of-care diagnostics. Such systems offer to dramatically reduce liquid sample and reagent quantities, increase sensitivity as well as speed of analysis and facilitate portable systems via the integration of components such as pumps, valves, mixers, separation units, reactors and detectors. Precise microfluidic control for such systems has long been considered one of the most difficult technical barriers due to integration of on-chip fluidic handling components and complicated off-chip liquid control as well as fluidic interconnections. Actuation principles and materials with the advantages of low cost, easy fabrication, easy integration, high reliability, and compact size are required to promote the development of such systems. Within this thesis, liquid displacement in microfluidic applications, by means of expandable microspheres, is presented as an innovative approach addressing some of the previously mentioned issues. Furthermore, these expandable microspheres are embedded into a PDMS matrix, which composes a novel thermally responsive silicone elastomer composite actuator for liquid handling. Due to the merits of PDMS and expandable microspheres, the composite actuator's main characteristic to expand irreversibly upon generated heat makes it possible to locally alter its surface topography. The composite actuator concept, along with a novel adhesive PDMS bonding technique, is used to design and fabricate liquid handling components such as pumps and valves, which operate at work-ranges from nanoliters to microliters. The integration of several such microfluidic components promotes the development of disposable lab-on-a-chip platforms for precise sample volume control addressing, e.g. active dosing, transportation, merging and mixing of nanoliter liquid volumes. Moreover, microfluidic pumps based on the composite actuator have been incorporated with sharp and hollow microneedles to realize a microneedle-based transdermal patch which exhibits on-board liquid storage and active dispensing functionality. Such a system represents a first step toward painless, minimally invasive and transdermal administration of macromolecular drugs such as insulin or vaccines. The presented on-chip liquid handling concept does not require external actuators for pumping and valving, uses low-cost materials and wafer-level processes only, is highly integrable and potentially enables controlled and cost-effective transdermal microfluidic applications, as well as large-scale integrated fluidic networks for point-of care diagnostics, disposable biochips or lab-on-a-chip applications. This thesis discusses several design concepts for a large variety of microfluidic components, which are promoted by the use of the novel composite actuator. Results on the successful fabrication and evaluation of prototype devices are reported herein along with comprehensive process parameters on a novel full-wafer adhesive bonding technique for the fabrication of PDMS based microfluidic devices. / QC 20100817

With the completion of the human genome sequencing project, attention is currently shifting toward understanding how genetic variation, such as single nucleotide polymorphism (SNP), leads to disease. To identify, understand, and control biological mechanisms of living organisms, the enormous amounts of accumulated sequence information must be coupled to faster, cheaper, and more powerful technologies for DNA, RNA, and protein analysis. One approach is the miniaturization of analytical methods through the application of microfluidics, which involves the manipulation of fluids in micrometer-sized channels. Advances in microfluidic chip technology are expected to play a major role in the development of cost-effective and rapid DNA analysis methods. This thesis presents microfluidic approaches for different DNA genotyping assays. The overall goal is to combine the potential of the microfluidic lab-on-a-chip concept with biochemistry to develop and improve current methods for SNP genotyping. Three genotyping assays using miniaturized microfluidic approaches are addressed. The first two assays are based on primer extension by DNA polymerase. A microfluidic device consisting of a flow-through filter chamber for handling beads with nanoliter liquid volumes was used in these studies. The first assay involved an allelespecific extension strategy. The microfluidic approach took advantage of the different reaction kinetics of matched and mismatched configurations at the 3’-ends of a primer/template complex. The second assay consisted of adapting pyrosequencing technology, a bioluminometric DNA sequencing assay based on sequencing-bysynthesis, to a microfluidic flow-through platform. Base-by-base sequencing was performed in a microfluidic device to obtain accurate SNP scoring data on nanoliter volumes. This thesis also presents the applications of monolayer of beads immobilized by microcontact printing for chip-based DNA analysis. Single-base incorporation could be detected with pyrosequencing chemistry on these monolayers. The third assay developed is based on a hybridization technology termed Dynamic Allele-Specific Hybridization (DASH). In this approach, monolayered beads containing DNA duplexes were randomly immobilized on the surface of a microheater chip. DNA melting-curve analysis was performed by dynamically heating the chip while simultaneously monitoring the DNA denaturation profile to determine the genotype. Multiplexing based on single-bead analysis was achieved at heating rates more than 20 times faster than conventional DASH provides. / QC 20101008

Die vorliegende Dissertation beschreibt die Erarbeitung anwendbarer Methoden zum Aufbau Oberflächenplasmonenresonanz (SPR)-basierter DNA-Mikroarrays. Es werden die Beziehungen zwischen allen Teilschritten der Entwicklung eines DNA-Biosensors aufgezeigt. Die Sondendichte auf der Sensoroberfläche ist entscheidend für die Leistungsfähigkeit eines DNA-Chips. In dieser Arbeit werden thiolmodifizierte Sonden und solche mit Phosphorothioatgruppen verwendet und verglichen. Der Aufbau selbstorganisierender Monoschichten, bestehend aus Mercaptoalkoholen und thiolmodifizierten DNA-Einzelsträngen, wird mittels Röntgenphotoelektronenspektroskopie untersucht. Es werden bis zu 180 Spots auf einem SPR-Chip aufgetragen. Eine weitere Erhöhung der Anzahl an Sondenorten pro Chip wird mit einer hydrophil/hydrophoben Strukturierung der Arrayoberfläche erreicht. Dies erfolgt durch das Mikrokontaktdrucken mit Alkanthiolen. Die selektiven Hybridisierungen der Produkte der Polymerase-Kettenreaktion (PCR) werden bei SPR-Messungen auf DNA-Mikroarrays detektiert. Eine schnelle markierungsfreie Echtzeitanalyse wird bei Hybridisierungen im mikrofluidischen Kanal innerhalb weniger Minuten erzielt. Die Anwendbarkeit dieser Methoden wurde anhand der Mutationsanalyse der Fusionsgene AML1-ETO und CBFB-MYH11 bei der akuten myeloischen Leukämie bestätigt. Die Hybridisierungseffizienz auf DNA-Mikroarrays hängt stark von der Sodensequenz ab. SPR-Experimente zeigen, dass die Ausbildung der Haarnadelstrukturen die Ursache dafür ist. Ein Computerprogramm (EGNAS) auf Grundlage eines neu entwickelten Nucleobasen-Sequenzentwurf-Algorithmus, ermöglicht die Generierung vollständiger Sequenzsätze. Die Intra- und Interstrangeigenschaften dieser Sequenzen können kontrolliert werden, um Haarnadelstrukturen und Kreuzhybridisierungen zu vermeiden. Dadurch können optimierte Sequenzen für Anwendungen auf DNA-Chips oder in der DNA-Nanobiotechnologie entworfen werden.