<p>During the past two decades, soft lithographic techniques that circumvent the limitations of photolithography have emerged as important tools for the transfer of patterns with sub-micron dimensions. Among these techniques, microcontact printing (uCP) has shown special promise. In uCP, an elastomeric stamp is first inked with surface-reactive molecules and placed in contact with an ink-reactive surface, resulting in pattern transfer in the form of self-assembled monolayers in regions of conformal contact. The resolution in uCP is ultimately limited to the diffusion of ink and the elastomechanical properties of the bulk stamping material. </p> <p>One way to improve resolution is to eliminate diffusion by using inkless methods for pattern transfer. Inkless catalytic-uCP uses a chemical reaction between a stamp-immobilized catalyst and surface bearing cognate substrate to transfer pattern in the areas of conformal contact. By using pre-assembled cognate surfaces, the approach extends the range of surfaces readily amenable to patterning while obviating diffusive resolution limits imposed by traditional uCP. </p> <p>In this thesis, we report two methods using inkless catalytic uCP: biocatalytic-uCP utilizes an immobilized enzyme as a catalyst whereas catalytic-uCP utilizes an immobilized small molecule as a catalyst, such as an acid or base. Both catalytic techniques demonstrate pattern transfer at the microscale while using unconventional, acrylate-based stamp materials. Previous results produced with catalytic-uCP have shown pattern transfer with sub-50 nm edge resolution. In this demonstration of catalytic-uCP, we use the technique to demonstrate a bi-layered patterning technique for H-terminated silicon, the foremost material in semi-conductor fabrication. This technique simultaneously protects the underlying silicon surface from degradation while a highly-reactive organic overlayer remains patternable by acidic-functionalized PU stamps. Lines bearing widths as small as 150 nm were reproduced on the reactive SAM overlayer, which would not be possible without circumvention of diffusion. Before and after patterning, no oxidation of the underlying silicon was observed, preserving desired electronic properties throughout the whole process. This bi-patterning technique could be extended to other technologically-relevant surfaces for further application in organic-based electronic devices and other related technologies.</p> / Dissertation

The advent of numerous tools, ease of techniques, and concepts related to nanotechnology, in combination with functionalization via simple chemistry has made gold important for various biomedical applications. In this dissertation, the development and characterization of planar gold surfaces with responsive hydrogel patterns for rapid point of care sensing and the functionalization of gold nanoparticles for drug delivery are highlighted. Biomedical micro- and nanoscale devices that are spatially functionalized with intelligent hydrogels are typically fabricated using conventional UV-lithography. Herein, precise 3-D hydrogel patterns made up of temperature responsive crosslinked poly(N-isopropylacrylamide) over gold were synthesized. The XY control of the hydrogel was achieved using microcontact printing, while thickness control was achieved using atom transfer radical polymerization (ATRP). Atomic force microscopy analysis showed that to the ATRP reaction time governed the pattern growth. The temperature dependent swelling ratio was tailored by tuning the mesh size of the hydrogel. While nanopatterns exhibited a broad lower critical solution temperature (LCST) transition, surface roughness showed a sharp LCST transition. Quartz crystal microbalance with dissipation showed rapid response behavior of the thin films, which makes them applicable as functional components in biomedical devices. The easy synthesis, relative biocompatibility, inertness, and easy functionalization of gold nanoparticles (GNPs) have made them useful for various biomedical applications. Although ATRP can be successfully carried out over GNPs, the yield of stable solution based GNPs for biomedical applications prove to be low. As an alternative approach, a novel method of ISOlating, FUnctionalizing, and REleasing nanoparticles (ISOFURE) was proposed. Biodegradable poly(β-amino ester) hydrogels were used to synthesize ISOFURE-GNP composites. ATRP was performed inside the composite, and the final hydrogel coated GNPs were released via matrix degradation. Response analysis confirmed that the ISOFURE method led to the increased stability and yield of the hydrogel coated ISOFURE-GNPs. The ISOFURE protocol was also utilized in functionalizing GNPs with enzyme catalase in the absence of a stabilizing reagent. Biotin-streptavidin affinity was used as the bioconjugation method. Activity analysis of the conjugated enzyme showed that the ISOFURE-GNPs showed enhanced biomolecular loading relative to solution based stabilizing reagent passivated GNPs.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22776号 / 工博第4775号 / 新制||工||1747(附属図書館) / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 杉村 博之, 教授 邑瀬 邦明, 教授 宇田 哲也 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Trilayer polypyrrole microactuators that can operate in air have previously been developed. They consist of two outer layers ofthe electroactive polymer polypyrrole (PPy) and one inner layer of a porous poly(vinylidene flouride) (PVDF) membranecontaining a liquid electrolyte. The two outer layers of PPy are each connected with gold electrodes and separated by the porousPVDF membrane. This microtool is fabricated by bottom-up microfabrication However, porous PVDF layer is not compatible with bottom upmicrofabrication and highly swollen SPE suffers from gold electrode delamination. Hence, in this MSc project/thesis a novelmethod of flexible electrode fabrication with conducting polymers was developed by soft lithography and drop-on-demandprinting. The gold electrodes were replaced by patterned vapor phase polymerized (VPP) poly(3,4-ethylenedioxythiophene) (PEDOT)electrodes due to its high electrical conductivity and versatile process ability. The replacement of the stiff gold electrodes byflexible and stretchable PEDOT allowed high volume change of the material and motions. The PEDOT electrodes werefabricated by patterning the oxidant iron tosylate using microcontact printing and drop-on-demand printing. Moreover, thePVDF membrane has been replaced by a nitrile butadiene rubber/poly(ethylene oxide) semi-interpenetrating polymer network(IPN) to increase ion conductivity and strechability and hence actuator performance.

L'enjeu de ce travail est la réalisation de circuits électroniques sur des pièces polymères injectées à forme 3D, appelées MIDs, par microtamponnage (μTP). Le μTP, est une technique de localisation de substances (chimiques ou biologiques) par contact mécanique d'un tampon structuré sur un substrat. Il permet de localiser les pistes conductrices des MIDs en utilisant deux protocoles : le μTP passif et le μTP actif. La première méthode consiste à déposer de manière localisée un thiol par μTP sur la surface de la pièce préalablement métallisée. Le thiol permet de protéger les pistes métalliques qui doivent être conservées après gravure humide. Dans la seconde, un catalyseur (du palladium) est déposé par μTP, suivi de la métallisation electroless des pistes. La problématique du μTP 3D a été étudiée à l'aide d'un tampon épousant la forme de la pièce. Nos résultats expérimentaux couplés à des simulations par éléments finis de la déformation du tampon lors de sa compression au moment du contact avec la pièce, nous ont permis de déterminer les paramètres clefs du procédé : l'alignement du tampon par rapport à la pièce, la gestion du contact et la fabrication du tampon. Il a été mis en évidence que la tolérance de l'alignement est de l'ordre de 100μm pour des motifs structurés de 250μm de hauteur. Un tampon composé d'un support rigide surmonté d'une couche mince structurée permet de limiter ses déformations lors de sa compression. Les enseignements tirés nous ont permis de réaliser nos premiers circuits par μTP à l'aide d'une machine originale développée au laboratoire. La problématique de l'épaississement des couches de cuivre adhérentes sur des pièces en LCP est également abordée, un protocole d'épaississement ayant été validé / The main challenge of this work was the production of electronic circuits on injected 3Dshaped polymer components, called MIDs, by microcontact printing (μCP). μCP is a substance (chemical or biological) localisation technique through mechanical contact between a patterned stamp and a substrate. It enables the MIDs’ conductor tracks to be located using two techniques: passive μCP and active μCP. The first method involves locally depositing a thiol by μCP on the substrate’s surface, which has previously been coated with a thin metallic film. The thiol protects the metallic tracks, which must be preserved after wet chemical etching. Regarding the second method, a catalyst (palladium) is deposited by μCP, followed by the electroless metallization of the tracks. The 3D μCP issue was studied using a stamp, which matched the shape of the substrate. Our experimental results combined with finite element simulations of stamp deformation during compression and whilst in contact with the substrate, revealed the key parameters of the process: stamp/substrate alignment, contact control and stamp manufacturing. We found that the alignment tolerance was around 100μm for a 250μm thickness structured design. A stamp with a rigid support covered in a structured thin film minimises deformation during compression. Thanks to the lessons learned, we carried out our first circuits using μCP with a new machine, which was developed in the laboratory. We also addressed the problem of thickening adhesive copper layers on LCP components, as a thickening procedure had already been validated

We reported a non-crosslinking approach to synthesize nitroxide radical polymer brushes for thin-film electrodes via surface-initiated atom transfer radical polymeization (SI-ATRP), which was effective to yield the organic radical polymer brushes with high grafting density and to attain a uniform surface. As mentioned above, the covalent bonding of nitroxide polymer brushes to the conducting substrate not only prevented the polymer dissolution into organic electrolyte solution but improved the cycle life performance of batteries. Moreover, they can be the potential application in microbatteries by using microcontact printing to produce the patterned nitroxide polymer brushes on a conducting substrate. Even though the organic radical polymer brushes provided a new approach to syn-thesize thin-film electrodes, they still existed many problems that needed to study and to figure out. We discussed the morphology and electrochemical performance about ni-troxide radical polymer in the thesis. In the measurement of surface properties, we used the contact angle, electron spectroscopy for chemical analysis (ESCA) and atomic force microscopic (AFM) to proceed. Another, in the measurement of electrochemical analysis, we used the cyclic voltammetry(CV), alternating current (AC) impedance and charge-discharge to understand the regarding mechanism in this polymer layer during the electrochemical reaction. In chapter 4, we discussed the oxidative problem in the polymer brushes. It should be well controlled during the oxidation reaction, because the oxidation level may affect the diffusion of electron that resulted the capacity better or not. In chapter5, we controlled the density of polymer brushes to construct the possible mechanism during the electro-chemical reaction, and found out the possible factors that affected the electrochemistry. In chapter 6, we applied the better results from the front chapter to the organic radical battery, and compared their electrical performance.

L'objectif des travaux est de démontrer que la lithographie douce, quelquefois baptisée " Micro-Contcat Printing (µCP)", constitue une méthode de dépôt de biomolécules présentant de nombreux avantages pour des applications de type Biopuces. Pour la fabrication de puces à ADN, nous démontrons que le µCP est une technique compétitive par rapport au dépôt robotisé de gouttes traditionnellement utilisé. Le coût est inférieur, la densité des puces est augmentée et la qualité et la définition des motifs biomoléculaires sont supérieures. Une étude complète des mécanismes d'encrage des timbres élastomères d'impression ainsi que des mécanismes de transfert par contact des molécules vers le substrat est présentée. Le rôle prépondérant des fragments de polymère non réticulés présents à la surface des timbres est mis en évidence. Dans un second volet nous étudions la possibilité de générer par la même méthode des puces à biomolécules uniques. Nous montrons comment le µCP peut être poussé jusqu'à une résolution sub-micrométrique proche de 50 nm. Deux voies technologiques originales impliquant la lithographie douce sont proposées : l'une pour peigner individuellement en des sites organisés précisément sur la surface des longs brins d'ADN pour des études de génétique, l'autre pour fixer des molécules individuelles d'ADN par une extrémité rendant possible l'étude dynamique de molécules uniques (ADN) sur de larges populations.

Les techniques non-conventionnelles de lithographie ont fait depuis deux décennies une entrée remarquée dans les sciences de l'ingénierie. Elles sont considérées aujourd'hui comme un enjeu majeur pour le développement des dispositifs. L'objectif principal de cette thèse est d'explorer de nouvelles voies pour la conception des micro&nanabiocapteurs en procédant à des impressions de poly(pyrrole) (PPy) à haute résolution par microtamponnage assisté par polymérisation catalytique (nanoCP-CCP) sur des substrats polymériques (poly(téréphtalate) d'éthylène (PETE), Copolymère d'oléfine cyclique (COC), polyétheréthercétone (PEEK), poly(éthylène 2,6-naphtalate (PEN) et le polyamide (PI)). Dans un premier temps, nous avons mis au point différentes techniques d'impression (greffage par impression, impression adressée et impression directe) et des conditions de polymérisation pour moduler les caractéristiques de PPy micro et nano-structurés, afin de contrôler la taille, la forme et les propriétés électriques désirées. Nous avons constaté que les paramètres les plus importants qui influent sur le processus d'impression surtout à l'échelle nanométrique sont: a) Le rapport des concentrations des réactifs pour le procédé de polymérisation qui comprend le Py-silane, nitrate d'argent (AgNO3), le chlorure du fer (III)/ le chlorure de Lithium (FeCl3/LiCl). b) Les paramètres physiques de la machine GeSIM; la pression d'impression, le niveau de contact, le temps d'encrage du tampon polydiméthylesiloxane (PDMS), et le temps d'impression. Finalement, on est arrivé à fabriquer des nanofils de PPy (PPy-NF) de 747±12,2 nm de largeur, 114±8 nm de hauteur et avec une séparation de 573±13,4 nm entre deux PPy-NF consécutifs. Ces films micro et nano-structurés ont été caractérisées par microscopie électronique à balayage (SEM), microscopie à force atomique (AFM) et spectrométrie de photon-électrons induits par rayons X (XPS). Dans une deuxième partie, on a développé des immunocapteurs à base de PPy-NF sensible aux biomarqueurs interleukine 8 et 6. Pour cela, différentes stratégies ont été adoptées pour immobiliser les anticorps spécifiques à ces deux biomarqueurs. Ces immunocapteurs ont été caractérisés par la méthode de spectroscopie d'impédance électrochimique (EIS). Les résultats obtenus par rapport à la sensibilité et la sélectivité sont très satisfaisants avec des limites de détection de l'ordre de quelques pg/L pour les deux immunocapteurs développés / Non-conventional lithography techniques have made for the two last decades a huge impact in the engineering sciences. They are now regarded as a main challenge for the development of the devices. The objective of this thesis is to explore new alternative possibilities for designing micro & nano biosensors based on poly(pyrrole) (PPy) high resolution microprinting attended by catalytic polymerization (nanoCP-CCP) on substrates Polymer (poly (terephthalate) ethylene (PETE), cyclic olefin copolymer (COC), polyetheretherketone (PEEK), poly (ethylene 2,6-naphthalate (PEN), and polyamide (PI)). In a first step We have developed various printing techniques (grafting printing, addressed printing and direct printing) and polymerization conditions to modulate the characteristics of PPy micro and nano-structured in order to control the size, shape and Electrical desired properties. We found that the most important parameters that affect the printing process especially at the nanoscale are: a.) The ratio of the concentrations of reagents for the polymerization process which includes the Py-silane, nitrate silver (AgNO3), iron chloride (III) / lithium chloride (FeCl3 / LiCl). b) The physical parameters of the GeSIM machine; the printing pressure, contact level, the inking time stamp of polydimethylsiloxane (PDMS), and printing time. Finally, we got to manufacture PPy nanowires (PPy-NW) 747 ± 12.2 nm wide, 114 ± 8 nm in height and with a separation of 573 ± 13.4 nm between two consecutive PPy-NW. These micro and nano-structured films were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and electron-photon spectroscopy induced by X-rays (XPS). In the second part, we have developed a PPy-NW-based immunosensors sensitive to interleukin 8 and 6 biomarkers. For this, different strategies have been adopted to immobilize antibodies specific to these two biomarkers. These immunosensors were characterized by electrochemical impedance spectroscopy method (EIS). The results obtained in relation to the sensitivity and selectivity are very satisfactory with the security detection limits of a few pg / L for both developed immunosensors

L’étude des propriétés singulières de nanoparticules colloïdales synthétisées par voie chimique et leur intégration dans des nano-composants requiert leur assemblage dirigé sur des zones parfaitement définies et localisées de surfaces solides. L’objet de cette thèse est le développement d’une méthode d’assemblage dirigé originale: la nanoxérographie par microscope à force atomique (AFM). Cette technique consiste à injecter localement, sur des zones spécifiques, des charges électrostatiques dans un matériau électret par l’intermédiaire d’une pointe d’AFM. Ces charges servent ensuite de pièges électrostatiques sur la surface pour les nanoparticules en solution. Dans le cadre de ce travail, l’injection, la rétention de charges dans de fines couches électrets de PolyMéthylMéthAcrylate (PMMA) et la quantification des densités de charges surfaciques des motifs chargés, ont été étudiées grâce au mode électrique dérivé de l’AFM, le microscope à force Kelvin (KFM). L’étude de l’assemblage de nanoparticules de différentes natures (métal, polymère (organique ou inorganique)), de taille moyenne variable dans un large domaine (2 nm - 1µm) et de potentiel zêta contrôlé a permis d’analyser les mécanismes de dépôt et de montrer les performances de la méthode et son aspect générique. Enfin deux techniques d’injection de charges parallèles ont été mises en place afin d’offrir des perspectives industrielles: le microcontact printing électrique et la nanoimpression électrique / The study of original properties of colloidal nanoparticles and their integration into nanodevices requires their assembly onto specific areas of solid surfaces. The aim of this thesis work is to develop an innovative method for the directed assembly of colloidal nanoparticles: the nanoxerography process by atomic force microscope (AFM). This technique consists in injecting charges into electrets using an AFM tip. The injected charges are then used to electrostatically trap nanoparticles from suspensions onto the surface. In this context, the charge writing and charge decay in PolyMethyMethAcrylate (PMMA) thin films were studied and the charge density of the charged patterns were quantified using Kelvin force microscope (KFM), an electrical mode of AFM. Assemblies of nanoparticles of different nature (metallic, polymeric (organic and inorganic)), with average sizes extending over a large range (2 nm to 1 µm) and controlled zeta potential were obtained on PMMA thin films. This allowed the analysis of assembly mechanisms and demonstration of the excellent performance of the method. Finally, two techniques of parallel charge writing, viz., the electrical microcontact printing and the electrical nanoimprinting were explored with the prospect of extending the nanoxerography process to industrial scale

Bone repair is modulated by different stimuli. There is evidence that the Transforming Growth Factor-beta (TGF-¿) 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-¿s, 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-¿1, 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-¿s and their solvent and carrier influenced wound closure in an in vitro wound closure model and how TGF-¿s influence ECM secretion and integrin expression. 5, 10, 25, 50 and 100¿m 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 50¿m and 100¿m 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 50¿m 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 100¿m 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-¿1, 2 and 3 all decreased cell attachment, but this effect was significantly greater in the case of HCl and TGF-¿3 (p<0.001). However, there were significant differences in trypsinisation rates between HCl and TGF-¿3 (p<0.001). The wound healing response to the TGF-¿s and their solvent/carrier was also investigated in 300¿m ± 10-30¿m SD wide model wounds induced in fully confluent monolayers of MG63 bone cells. The results indicated that TGF-¿3 and HCl significantly enhance wound closure when compared against negative controls, TGF-¿1 and TGF-¿2 treatment (p<0.001). It was also found that TGF-¿1 and TGF-¿2 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 20¿M, 40¿M, 80¿M and 160¿M concentrations of HCl prior to wounding and wound closure rates were recorded. Wound closure was dependent on HCl dose with the 80¿M and 160¿M concentrations inducing increases in wound closure rates that were both significantly greater than those induced by 20¿M, 40¿M and control treatments (p<0.001). However, there were significant differences in wound closure between the 80¿M and 160¿M treatment groups after 30hrs of treatment (p<0.001). The effect of different TGF-¿ 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-¿(2+3) and TGF-¿(1+3) (p<0.001). Any cell treated with TGF-¿1, TGF-¿(1+2) and TGF-¿(1+2+3) showed significantly less elongation compared to the control and other TGF-¿ isomers. In terms of proliferation rate, TGF-¿3 and TGF-¿(2+3) increased cell numbers more than TGF-¿1, TGF-¿2 and other combinations. TGF-¿1 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-¿3 significantly promoted the secretion of collagen type I and anti-human fibronectin in addition to integrin (¿3 and ¿1) expression. Statistically TGF-¿3 and their combinations showed significant differences in number of cells stained for collagen type I, anti-human fibronectin, ¿3 and ¿1integrin. Any cell treated with TGF-¿1 or any combination with TGF-¿1 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-¿s influenced the distribution of focal contacts. In the case of TGF-¿1 treated cells the bright high contrast regions were intense but only arranged around the periphery of the cell. In TGF-¿2 and TGF-¿3 cells the bright contrast regions were weaker but again mostly localised around the periphery. These findings supported the earlier trypsinisation results.