De par leur qualité d’accumulation de triacylglycérol (TAG) sous forme de gouttelettes lipidiques (LDs) lors destress abiotiques, les microalgues oléagineuses se sont imposées comme des modèles d’études d’intérêt pour denombreuses applications biotechnologiques (nutrition, chimie verte, biocarburants, santé humaine). Ces stresssont cependant responsables d’un arrêt de la croissance et de production de biomasse. Un criblage de petitesmolécules visant à favoriser l’accumulation de TAG chez la diatomée Phaeodactylum a mis en lumière 34composés connus pour agir sur certaines voies métaboliques de signalisation. Une étude approfondie des effetsdu 17α-éthynylestradiol est proposée. La mise en lumières de composés ciblant les nucléotides cycliques et lesoxylipines nous a conduit à réévaluer les effets du monoxyde d’azote (NO.) et à détecter la présenced’isoprostanoïdes après un stress oxydant chez Phaeodactylum.Les LDs sont des structures conservées, des procaryotes jusqu’aux endosymbiontes secondaires, présentant uncoeur hydrophobe entouré d’une monocouche de lipides polaires dans laquelle s’enchâssent des protéines defaçon transitoire ou permanente. Ces protéines peuvent jouer un rôle structural ou être impliquées dans labiologie de la gouttelette. Après optimisation d’un protocole de purification, nous avons déterminé leglycérolipidome et le protéome de la LD de Phaeodactylum. Le coeur hydrophobe des LDs est constituéuniquement de TAG entouré d’une monocouche de lipides polaires composée de phosphatidylcholine (PC),sulfoquinovosyldiacylglycérol (SQDG) et de deux espèces moléculaires (20:5-16:1 et 20:5-16:2) de DGTA, unbétaine lipide. Un stérol libre localisé probablement dans la monocouche, le brassicastérol, a été égalementdétecté. Un enrichissement spécifique en β-carotène a été observé. Le protéome de la LD est composé de 86protéines incluant notamment la LD-protéine StLDP, des acteurs du métabolisme, des protéines associées à desorganites membranaires, au traitement de l’information génétique ou encore des chaperonnes impliquées dans lecontrôle qualité des protéines. Ces travaux nous éclairent sur la biogenèse et la découverte de possiblesnouvelles fonctionnalités de la LD de Phaeodactylum. Nous proposons un nouveau modèle architectural pour laLD nous interrogeant sur ses origines. Des perspectives d’études, pour la caractérisation fonctionnelle desacteurs protéiques de la LD et sur une relocalisation de la LD vers la membrane plasmique pour favoriser sonextraction, sont proposées. / Due to their quality of triacylglycerol (TAG) content in the form of lipid droplets (LDs) accumulating upon abioticstresses, microalgae have emerged as models of interest for many biotechnological applications (nutrition, greenchemistry, biofuels, human health). These stresses, however, are responsible for a growth arrest and lowbiomass yield. A phenotypic screen of small molecules triggering TAG accumulation in Phaeodactylumhighlighted 34 compounds known to act on specific metabolic and signaling pathways. A detailed study of theeffects of 17α-ethynylestradiol is proposed. The identification of compounds interfering with cyclic nucleotides andoxylipins led us to re-evaluate the effects of nitric oxide (NO.) and to characterize the activity of isoprostanoidsafter oxidative stress in the diatom Phaeodactylum.LDs are subcellular structures, conserved from prokaryotes to secondary endosymbionts, containing ahydrophobic core surrounded by a monolayer of polar lipids to which proteins transiently or permanentlyassociate. These proteins may play a structural role or be involved in the function of the droplet. After optimizationof a purification protocol, we determined the glycerolipidome and the proteome of the LD of Phaeodactylum. Thehydrophobic core is only made of TAG surrounded by a monolayer of polar lipids consisting ofphosphatidylcholine (PC), sulfoquinovosyldiacylglycerol (SQDG) and two molecular species (20:5-16:1 and 20:5-16:2) of DGTA, a betaine lipid. A sterol probably located in the monolayer, brassicasterol, was also detected.Specific enrichment of β-carotene has been observed. The proteome of the LD is composed of 86 proteinsincluding most notably the LD-protein StLDP, metabolic actors, organelle membrane associated proteins, proteinsimplicated in the treatment of genetic information or chaperones involved in protein quality control. This thesisallows us a better understanding of the biogenesis and the discovery of possible new functionalities of thePhaeodactylum LD. We propose an architectural model for the LD, and address the question of its origins. Futureprospects on the functional characterization of LD proteins and relocation of LD to the plasma membrane topromote its extraction are proposed.

This thesis investigates the applicability of novel approaches designed to study the molecular mechanisms required for the initiation of organogenesis within the early endoderm. The endoderm is the germ layer that gives rise to the gut-tube and associated organs including the thyroid, lung, liver and pancreas. Our laboratory focuses on understanding the molecular mechanisms governing the developmental transition from endoderm to liver and pancreas. Several signaling pathways including Wnt, Retinoic Acid (RA), Bone Morphogenetic Protein (BMP) and Transforming Growth Factor-β (TGFβ) have been implicated in the emergence of the liver bud from the endoderm in the mouse or other vertebrate species. However, neither the exact signals nor the precise roles during budding process have been identified, due to the complexity of specifically altering these essential pathways using traditional genetic approaches during the earliest stages of endoderm organogenesis. These traditional techniques include transgenic, knockout or conditional knockouts strategies. To overcome the difficulties of genetic accessibility, our laboratory has optimized two complementary approaches, electroporation and addition of activators or inhibitors directly to the culture media, to study the earliest stages of organ formation using an ex vivo culture system (whole embryo culture), that allow us for normal embryonic development for up to two days. This ex-vivo technique also provides the opportunity to access and manipulate the endoderm, specifically the liver and pancreas precursor cells, prior to organ specification. Because the endoderm undergoes normal liver and pancreas specification in our ex vivo system by 24 hours after culture begin, we reason that it is possible to manipulate gene expression at the onset of culture. We then determine the effects of this manipulation on liver or pancreas development by molecular and morphological analysis after culture. The first approach we developed is the use of directional electroporation of nucleic acids to manipulate a specific region of the endoderm, particularly on liver and pancreas developmental processes. The second method is global inhibition or activation using inhibitors or growth factors activators, focusing on the TGFβ signaling pathway. These techniques will be performed prior to, or concurrent with, liver and pancreas specification, followed by embryo culture until after the onset of organogenesis. The combination of these techniques constitutes a practical approach to stage-manage the endoderm in a temporally and spatially distinct manner. In addition, it will allow us to alter specific signaling pathways without the labor-intensive generation of genetically modified animals. Indeed, establishment of these methodologies may provide a robust tool for rapid screening of candidate genes and signaling molecules underlying organogenesis in any endodermally derived organ in mouse embryos.

No description available.

Anthrax is severe disease caused by the gram-positive Bacillus anthracis that can affect humans with deadly consequences. The disease propagates via the release of bacterial spores that can be naturally found in animals or can be weaponized and intentionally released into the atmosphere in a terrorist attack. Once inhaled, the spores become activated and the anthrax bacterium starts to reproduce and damage healthy macrophages by the release of the anthrax toxin. The anthrax toxin is composed of three virulent factors: (i) anthrax protective antigen (APA), (ii) anthrax lethal factor (ALF), and (iii) anthrax edema factor (AEF) that work in harmony to effectuate the lethality associated with the disease. Out of the two internalized factors, ALF has been identified to play a critical role in cell death. Studies in animals have shown that mice infected with an anthrax strain lacking ALF survive the infection whereas when ALF is present the survivability of the mice is eliminated. Although the current therapy for anthrax is antibiotic treatment, modern medicine faces some critical limitations when combating infections. Antibiotics have proven very efficient in eliminating the bacterial infection but they lack the ability to destroy or inhibit the toxins released by the bacteria. This is a significant problem since ALF can remain active in the body for days after the infection is eliminated with no way of inhibiting its destructive effects. The use of inhibitors of ALF is an attractive method to treat the pathogenesis of anthrax infections. Over the last decade several inhibitors of the enzymatic activity of ALF have been identified. In order to identify inhibitors of ALF a variety of screening approaches such as library screenings, Mass Spectroscopy- based screenings and scaffold-based NMR screening have been used. Results from these iv screening have yielded mainly small molecules that can inhibit ALF in low micromolar to nanomolar concentrations. Yet, although valuable, these results have very little significance with regards to treating ALF in a real-life scenario since pharmaceutical companies are not willing to invest in further developing these inhibitors. Furthermore, the low incidence of inhalation anthrax, the lack of a market for an ALF inhibitor, and the expenses associated with the approval process of the FDA, have hindered the motivation of pharmaceutical companies to pursuit these kind of drugs. Therefore we have screened a small-molecule library of FDA approved drugs and common molecules in order to identify currently approved FDA drugs that can also inhibit ALF (Chapter III). The screening revealed that five molecules: sulindac, fusaric acid, naproxen, ketoprofen and ibuprofen bound to either ALF or APA with sulindac binding both. Additionally, we have developed a nanoparticle-based screening method that assesses molecular interactions by magnetic relaxation changes (Chapter II). Using this assay, we were able to accurately measure the dissociation constants of different interactions between several ligands and macromolecules. Moreover, we have used computational docking studies to predict the binding site of the identified molecules on the ALF or APA (Chapter IV). These studies predicted that two molecules sulindac and fusaric acid could be potential inhibitors of ALF since they bind at the enzymatic pocket. As a result, we tested the inhibitory potential of these molecules as well as that of the metabolic derivatives of sulindac (Chapter V). Results from these studies provided conclusive evidence that fusaric acid and sulindac were both strong inhibitors of ALF. Furthermore, the metabolic derivatives of sulindac, sulindac sulfide and sulindac sulfone v also inhibited ALF. Overall, taking together these results we have discovered the alternate use of a currently used drug for the treatment of ALF pathogenesis.

It is known that organic monolayers on solid surfaces can enable electronic properties that are absent in the bulk of the solid materials. Often, once the organic film come into the contact with a solid surface, the established electronic interaction at their interface remains undisturbed. However, using a redox-active organic monolayer creates the possibility for modulating the extent and the direction of the interfacial charge transfer, establishing a switch at the interface. The theme of this thesis is investigation of the interfacial interaction of different redox states of a molecular switch, phenyl-capped aniline tetramer (PCAT) with iron oxide and graphite surfaces and their potential application in electronic devices. The nucleation and growth of submonolayer films of different oxidation states of PCAT on iron oxide surface was studied. Using atomic force microscopy and scaling island size distribution method the surface diffusion parameters of these islands were evaluated. Using X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy the changes in these organic monolayers before and after interaction with iron oxide were demonstrated. However, these techniques were unable to provide similar data from the solid surface side of the interface. Instead, we were able to demonstrate the changes in the iron oxide film as a result of interfacial charge transfer using electrical conductivity measurement techniques. Based on this information a microfluidic chemical sensor based on the interface of pencil film and PCAT for quantification of free chlorine in drinking water was constructed. Using XPS and UV-vis spectroscopy it was shown that the interaction the organic monolayer with sodium hypochlorite solution leads to the development of positive charges on the backbone of PCAT. This electrostatic charge can affect the charge transport in the pencil film causing the modulation of electrical conductivity of the film. The presented work demonstrates alternative pathways for the design of novel hybrid electronic devices based on thin molecular film and solid surfaces. / Thesis / Doctor of Philosophy (PhD)

Organic solar cells (OSCs) is an emerging photovoltaic technology that opens up new application areas where common inorganic techniques are not able to score. Some of those key features are flexibility, light weight, semitransparency, and low cost processing. The current industry-standard for the transparent electrode, indium tin oxide (ITO), cannot provide these properties because it is brittle and expensive. This thesis aims to investigate an alternative type of promising transparent electrode: silver nanowire (AgNW) networks. They exhibit similar or even better optical and electrical performance than ITO down to a sheet resistance of 12 Ohm/sq at 84% transmission (including the glass substrate). Furthermore, AgNWs are more flexible, solution-processable, and more cost-effective than ITO. However, two challenges occur during implementation as bottom electrode in OSCs. First, their inherently high roughness causes devices to shunt. Second, the AgNW network structure exhibits – in contrast to the continuous ITO – µm²-sized voids that have to be bridged electrically by the organic layers. In the first part of this thesis, solution-processed small molecule charge transport layers are investigated. In the case of hole transport layers (HTL), the host BF-DPB and the dopant NDP9 are investigated using tetrahydrofuran as a solvent. It is shown that BF-DPB is already doped by NDP9 in solution via the formation of a hybrid molecule complex. Solution-processed layers exhibit similar conductivities as compared to the reference deposition, which is thermal evaporation in high vacuum. The layers sufficiently smoothen the AgNW electrode such that DCV5T-Me:C60 organic solar cells with an efficiency up to 4.4% are obtained. Moreover, the influence of the square micrometer large network voids is investigated using HTLs of varying conductivity. As a result, a minimum conductivity of 1e−4 S/cm is needed to avoid macroscopic performance losses. Equivalent circuit simulations are performed to confirm these results. As a second planarization method, the AgNWs are buried in an insulating polymer that serves concurrently as flexible and ultrathin substrate. Out of three different polymers tested, the optical adhesive ’NOA63’ gives the best results. The roughness is strongly reduced from 30 nm down to (2 ± 1) nm. Two different OSC types are employed as testing devices with fully-flexible alumina encapsulation against moisture ingress. Maximum power conversion efficiencies of 5.0% and 5.6% are achieved with a fullerene-free cascade layer architecture and a DCV5T-Me:C60 OSC, respectively. To evaluate the applicability of these fully-flexible and encapsulated devices, degradation studies are performed under continuous illumination and a humid climate. Although employing the intrinsically stable DCV5T-Me:C60 stack design, within one day a fast degradation of the fully-flexible solar cells is observed. The degradation is attributed to AgNW electrode failure that results from photo-oxidation and -sulfurization, photo-migration, and electromigration. It is further shown that the cascade organic solar cell lacks intrinsic stability. In summary, efficient, fully-flexible, and encapsulated devices are shown. However, in terms of competitive OSCs, the low stability of AgNW electrodes is a challenge to be taken care of. In current research, this issue needs to be addressed more frequently. / Organische Solarzellen (OSZ) sind ein junges Forschungsgebiet der Photovoltaik, welches neue Anwendungsgebiete erschließt, für die herkömmliche anorganische Solarzellen nicht einsetzbar sind. Einige der Haupteigenschaften sind Flexibilität, niedriges Gewicht, Teiltransparenz und geringe Herstellungskosten. Indiumzinnoxid (ITO), der aktuelle Industriestandard transparenter Elektrodentechnologie, ist nicht in der Lage, diese Eigenschaften zu gewährleisten. Dies liegt vor allem an der Brüchigkeit von ITO und der begrenzten Verfügbarkeit von Indium, welche mit einem hohen Preis einhergeht. Das Ziel dieser Dissertation ist die Integration einer alternativen und vielversprechenden Elektrodentechnologie: Netzwerke aus Silbernanodrähten (AgNWs). Mit einem Schichtwiderstand von 12 Ohm/sq bei einer Transmission von 84% (inklusive Glassubstrat) besitzen sie ähnliche oder sogar bessere optische und elektrische Eigenschaften als ITO. Des Weiteren sind AgNW-Elektroden flexibler und kostengünstiger als ITO und aus flüssiger Phase prozessierbar. Es gibt allerdings zwei Herausforderungen, welche die Integration als Grundelektrode in OSZ erschweren. Zum einen sind AgNW-Netzwerke sehr rauh, sodass organische Bauteile kurzgeschlossen werden. Zum anderen weisen AgNW-Elektroden, im Gegensatz zu einer vollflächigen ITO-Schicht, Lücken zwischen den einzelnen Drähten auf. Diese Lücken müssen von den organischen Schichten der OSZ elektrisch überbrückt werden. Im ersten Teil der Arbeit werden daher flüssigprozessierte Ladungsträgertransportschichten aus kleinen Molekülen untersucht, welche die AgNW-Elektroden glätten und die verhältnismäßig großen Lücken füllen sollen. Im Falle von Lochleitschichten (HTL) wird BF-DPB als Matrix und NDP9 als Dotand in Tetrahydrofuran gelöst und zur Anwendung gebracht. BF-DPB wird dabei schon in Lösung von NDP9 dotiert, wobei sich ein Hybridmolekülkomplex ausbildet. Die Leitfähigkeit der entstehenden Schichten ist ähnlich zu Referenzschichten, die durch thermisches Verdampfen im Hochvakuum hergestellt wurden. Die erhaltenen HTLs glätten die AgNW-Elektroden, sodass DCV5T-Me:C60-Solarzellen mit einer Effizienz von maximal 4.4% hergestellt werden können. Weiterhin wird der Einfluss der quadratmikrometergroßen Löcher auf die makroskopische Effizienz der Solarzelle in Abhängigkeit der HTL Leitfähigkeit untersucht. Um signifikante Effizienzverluste zu verhindern, muss der HTL eine minimale Leitfähigkeit von etwa 1e−4 S/cm aufweisen. Simulationen eines Ersatzschaltkreises bestätigen hierbei die experimentellen Ergebnisse. Im zweiten Teil der Arbeit wird eine Planarisierungsmethode untersucht, in welcher die AgNWs in nichtleitfähigen Polymeren eingebettet werden. Diese Polymere fungieren anschließend als flexibles Substrat. Der optische Kleber ”NOA63” erzielt hierbei die besten Ergebnisse. Die Rauheit der AgNW-Elektroden wird von etwa 30 nm auf 1 bis 3 nm stark reduziert. Anschließend werden diese AgNW-Elektroden in zwei unterschiedlichen OSZ Konfigurationen getestet und mit einer vollflexiblen Schicht aus Aluminiumoxid gegen Wasserdampfpermeation verkapselt. Somit können maximale Effizienzen von 5% mithilfe einer organischen Kaskadenstruktur und 5.6% mit DCV5T-Me:C60 OSZ erreicht werden. Um die Anwendbarkeit dieser vollflexiblen und verkapselten OSZ zu bewerten, werden Alterungsstudien unter konstanter Beleuchtung und feuchtem Klima durchgeführt. Es wird gezeigt, dass die in das Polymer eingebettete AgNW-Elektrode aufgrund von Photooxidation und -schwefelung und Photo- und Elektromigration instabil ist. Dieser Sachverhalt ist für die Anwendung von AgNW-Elektroden in kommerziellen OSZ von großer Bedeutung und wurde in der Forschung bisher nicht ausreichend thematisiert.

Stable porcine ES cell lines have not been succesfully established yet. Ability to selfrenew or to differentiate has been limited in different porcine ES-like cell lines so far. PiPSCs represent an alternative to pESCs. PiPSCs can be generated by reprogramming of somatic cells by introduction of several transcription factors on viral vectors and were established by several groups. However, the majority of piPS cell lines depend on transgene expression because of incomplete reprogramming and weak activation of endogenous pluripotency genes. Transgene expression can infuence differentiation potential of piPSCs. Therefore, we have used integrative and reexcisable PiggyBac transposons to generate viral free piPSCs. At the same time, small molecules (low-molecular inhibitors) with potential to increase reprogramming efficiency and to activate endogenous pluripotency genes were used in the reprogramming media. This strategy has a potential for generation of naive piPSCs. Successful excision of transgenes would generate transgene-free piPSCs with uncompromised differentiation potential. Pig (Sus Scrofa) is at the same time an important animal model in preclinical stage research of the diseases. Somatic cells used for generation of piPSCs were isolated from pigs carrying mutated huntingtin. Integration of the...

<p>The discovery and utilization of novel starches with unique superb properties are highly demanded for modern industrial uses. Small-granule starch (SGS) is a category of unconventional starches with the granular size smaller than 10 μm. The potential use of SGS includes many conventional and novel high-value applications, such as texturizing, fat replacement, encapsulation, controlled delivery and nano-engineering. In the present work, we focused on three SGS isolated from amaranth (<i>Amaranth cruentus</i>), cow cockle (<i>Saponaria vaccaria</i>) and sweet corn (<i>sugary-1</i> maize mutant). The basic structural and unique physical properties of SGS were characterized and compared to common large-granule food starches. It was found that (1) the highly branched amylopectin contributed to low crystallinity and pasting viscosities of sweet corn starch, (2) cow cockle starch exhibited high shear-resistance and low retrogradation in prolonged storage, and (3) the amylopectin for amaranth starch was less branched with small clusters, which was associated with the high crystallinity, medium shear-resistance and low pasting viscosity of amaranth starch. Despite the small size of starch granules, SGS in both native and swelling states showed the capacity of retaining small molecules. Compared to large-granule starch, native SGS are more difficult for small molecules to reach an equilibrium permeation. This work provides insights to the fine structure and physicochemical behaviors of selected high-potent SGS, which is believed to support the industrial production and application of SGS in the future.</p> <p>The characteristics of local polymeric structure dominate many critical properties of glucan particles, such as starch retrogradation and the loading and stabilizing of active substance. Molecular rotor (MR), a fluorescent probe, was proposed to fulfill the simple, high-sensitive, and quantitative-based characterization of local glucan architecture (LGA). In the present work, two innovative studies relevant to this novel method were conducted: (1) MR was able to characterize glucans based on its unique fluorescent response to characteristic LGA, (2) MR was able to sensitively probe and visually demonstrate the transition of LGA induced by starch retrogradation. This novel MR-based approach is expected to advance carbohydrate-related researches in the future.</p>

O presente trabalho tem como dupla finalidade a determinação de algumas estruturas moleculares inéditas e o desenvolvimento de dois sistemas computacionais de uso em cristalografia. Primeiramente, determinamos quatro estruturas moleculares de complexos de ácido piridinacarboxílico ligados a íons metálicos (Co, Ni, Cu e Zn), os quais apresentam interesse farmacológico e se enquadram em uma das linhas de pesquisa do grupo de Cristalografia de São Carlos. Nesta Dissertação, a ênfase dada a esta parte do trabalho é a aprendizagem das técnicas relativamente complexas para a resolução e refinamento de estruturas moleculares obtidas através de difração de raios X, como uma motivação preliminar para o subseqüente trabalho computacional. Com relação ao desenvolvimento de sistemas computacionais, são apresentados dois programas que representam importantes ferramentas cristalográficas. O Xandrix realiza todos os cálculos matriciais necessários em transformações cristalográficas, tanto no espaço real como no recíproco, envolvendo tensores de até segunda ordem. O WinKabsch é uma implementação do algoritmo de Kabsch que melhor sobrepõe, utilizando mínimos quadrados, dois conjuntos de vetores e é usado para comparar moléculas inteiras ou fragmentos. Ambos foram desenvolvidos para ambiente Windows, oferecendo uma interface visual poderosa e amigável. O WinKabsch permite que o usuário gire, visualmente, duas moléculas dadas de maneira que elas se posicionem em orientações similares, para então selecionar, com o mouse, alguns átomos homólogos a partir dos quais é obtida uma primeira matriz de transformação. A seguir, o programa reconhece todos os outros pares de átomos homólogos para os cálculos finais. A transformação pode ser forçada a ser uma rotação própria quando as moléculas comparadas são suspeitas de possuir a mesma quiralidade. / This work has the two-fold purpose of determining a few novel crystal structures and to develop two computational systems for crystallographic use. First, we determined four molecular structures of complexes of a derivative of the pyridinacarboxilic acid with a metal ion (Co, Ni, Cu and Zn), which are of pharmacological interest and belong to one of the research lines of the group. In the present contribution the emphasis of these studies is in mastering the somewhat involved techniques for solving and refining molecular structures by X-ray diffraction, as a preliminary motivation for the subsequent computational work. Second, two programs which turn out to be useful tools for crystallographic work were developed. Xandrix, permits all matrix calculations necessary in crystallography transformations, both in real and reciprocal space, involving tensors up to the second rank. WinKabsch is an implementation of the Kabsch algorithm for the best least squares superposition of two sets of vectors and is used to compare molecules or molecular fragments. Both programs were developed to run in a Windows environment with a powerful and friendly visual interface. WinKabsch allows the user to visually rotate two given molecules to achieve similar orientations to perform later a mouse selection of a few homologous atoms from which a first orthogonal transformation matrix is obtained, after which the program recognizes all other pairs of homologous atoms for the final calculation. The transformation may be forced to be a proper rotation when the compared molecules are known to be of the same chirality.

Diese Arbeit befasst sich mit der Synthese und Charakterisierung von organolöslichen Thiophen und Benzodithiophen basierten Materialien und ihrer Anwendung als aktive lochleitende Halbleiterschichten in Feldeffekttransistoren. Im ersten Teil der Arbeit wird durch eine gezielte Modifikation des Thiophengrundgerüstes eine neue Comonomer-Einheit für die Synthese von Thiophen basierten Copolymeren erfolgreich dargestellt. Die hydrophoben Hexylgruppen in der 3-Position des Thiophens werden teilweise durch hydrophile 3,6-Dioxaheptylgruppen ersetzt. Über die Grignard-Metathese nach McCullough werden statistische Copolymere mit unterschiedlichen molaren Anteilen vom hydrophoben Hexyl- und hydrophilem 3,6-Dioxaheptylgruppen 1:1 (P-1), 1:2 (P-2) und 2:1 (P-3) erfolgreich hergestellt. Auch die Synthese eines definierten Blockcopolymers BP-1 durch sequentielle Addition der Comonomere wird realisiert. Optische und elektrochemische Eigenschaften der neuartigen Copolymere sind vergleichbar mit P3HT. Mit allen Copolymeren wird ein charakteristisches Transistorverhalten in einem Top-Gate/Bottom-Kontakt-Aufbau erhalten. Dabei werden mit P-1 als die aktive Halbleiterschicht im Bauteil, PMMA als Dielektrikum und Silber als Gate-Elektrode Mobilitäten von bis zu 10-2 cm2/Vs erzielt. Als Folge der optimierten Grenzfläche zwischen Dielektrikum und Halbleiter wird eine Verbesserung der Luftstabilität der Transistoren über mehrere Monate festgestellt. Im zweiten Teil der Arbeit werden Benzodithiophen basierte organische Materialien hergestellt. Für die Synthese der neuartigen Benzodithiophen-Derivate wird die Schlüsselverbindung TIPS-BDT in guter Ausbeute dargestellt. Die Difunktionalisierung von TIPS-BDT in den 2,6-Positionen über eine elektrophile Substitution liefert die gewünschten Dibrom- und Distannylmonomere. Zunächst werden über die Stille-Reaktion alternierende Copolymere mit alkylierten Fluoren- und Chinoxalin-Einheiten realisiert. Alle Copolymere zeichnen sich durch eine gute Löslichkeit in gängigen organischen Lösungsmitteln, hohe thermische Stabilität und durch gute Filmbildungseigenschaften aus. Des Weiteren sind alle Copolymere mit HOMO Lagen höher als -6.3 eV, verglichen mit den Thiophen basierten Copolymeren (P-1 bis P-3), sehr oxidationsstabil. Diese Copolymere zeigen amorphes Verhalten in den Halbleiterschichten in OFETs auf und es werden Mobilitäten bis zu 10-4 cm2/Vs erreicht. Eine Abhängigkeit der Bauteil-Leistung von dem Zinngehalt-Rest im Polymer wird nachgewiesen. Ein Zinngehalt von über 0.6 % kann enormen Einfluss auf die Mobilität ausüben, da die funktionellen SnMe3-Gruppen als Fallenzustände wirken können. Alternativ wird das alternierende TIPS-BDT/Fluoren-Copolymer P-5-Stille nach der Suzuki-Methode polymerisiert. Mit P-5-Suzuki als die aktive organische Halbleiterschicht im OFET wird die höchste Mobilität von 10-2 cm2/Vs erzielt. Diese Mobilität ist somit um zwei Größenordnungen höher als bei P-5-Stille, da die Fallenzustände in diesem Fall minimiert werden und folglich der Ladungstransport verbessert wird. Sowohl das Homopolymer P-12 als auch das Copolymer mit dem aromatischen Akzeptor Benzothiadiazol P-9 führen zu schwerlöslichen Polymeren. Aus diesem Grund werden einerseits Terpolymere aus TIPS-BDT/Fluoren/BTD-Einheiten P-10 und P-11 aufgebaut und andererseits wird versucht die TIPS-BDT-Einheit in die Seitenkette des Styrols einzubringen. Mit der Einführung von BTD in die Hauptpolymerkette werden insbesondere die Absorptions- und die elektrochemischen Eigenschaften beeinflusst. Im Vergleich zu dem TIPS-BDT/Fluoren-Copolymer reicht die Absorption bis in den sichtbaren Bereich und die LUMO Lage wird zu niederen Werten verschoben. Eine Verbesserung der Leistung in den Bauteilen wird jedoch nicht festgestellt. Die erfolgreiche erstmalige Synthese von TIPS-BDT als Seitenkettenpolymer an Styrol P-13 führt zu einem löslichen und amorphen Polymer mit vergleichbaren Mobilitäten von Styrol basierten Polymeren (µ = 10-5 cm2/Vs) im OFET. Ein weiteres Ziel dieser Arbeit ist die Synthese von niedermolekularen organolöslichen Benzodithiophen-Derivaten. Über Suzuki- und Stille-Reaktionen ist es erstmals möglich, verschiedenartige Aromaten über eine σ-Bindung an TIPS-BDT in den 2,6-Positionen zu knüpfen. Die UV/VIS-Untersuchungen zeigen, dass die Absorption durch die Verlängerung der π-Konjugationslänge zu höheren Wellenlängen verschoben wird. Darüber hinaus ist es möglich, thermisch vernetzbare Gruppen wie Allyloxy in das Molekülgerüst einzubauen. Das Einführen von F-Atomen in das Molekülgerüst resultiert in einer verstärkten Packungsordnung im Fluorbenzen funktionalisiertem TIPS-BDT (SM-4) im Festkörper mit sehr guten elektronischen Eigenschaften im OFET, wobei Mobilitäten bis zu 0.09 cm2/Vs erreicht werden. / This work describes the synthesis and characterization of organo-soluble thiophene and benzodithiophene based materials and their application as hole-transporting active semiconductor layers in field effect transistors. The first part of this work introduces the targeted modification of the thiophene base unit, obtaining new comonomers for the corresponding copolymers. The hydrophobic hexyl groups in the 3-position of thiophene are partially replaced by hydrophilic 3,6-Dioxaheptyl groups. Using the Grignard metathesis developed by McCullough, statistical copolymers with different molar ratios of hydrophobic and hydrophilic side groups 1:1 (P-1), 1:2 (P-2) and 2:1 (P-3) are synthesized. Furthermore a defined blockcopolymer is synthesized by a sequential comonomer addition. Optical and electrochemical properties of the novel copolymers are comparable to the homopolymer P3HT. All copolymers show clearly transistor characteristics in a top-gate/bottom-contact configuration. Devices with P-1 as active semiconductor layer, PMMA as dielectric and silver as the gate electrode show mobilities up to 10-2 cm2/Vs. As a result of the optimized semiconductor and dielectric interface an improvement of the air stability of the transistors is observed for several months. The second part describes the synthesis of benzodithiophene based organic materials. For the synthesis of the novel benzodithiophene-derivatives the key intermediate TIPS-BDT is obtained in high yields. A difunctionalization of TIPS-BDT in 2,6-position is observed by electrophilic substitution reactions and provided the desired dibromo- and distannyl-monomers. Via Stille-reaction alternated copolymers with alkylated fluorene and quinoxaline groups are synthesized. All copolymers are soluble in common organic solvents, show high thermal stability and good film forming properties. Furthermore all copolymers have HOMO values above -6.3 eV and are more oxidation stable compared to the thiophene based copolymers (P-1 up to P-3). These copolymers show an amorphous behavior as semiconductor layer in OFETs and mobilities up to 10-4 cm2/Vs are observed. A correlation between the device performance and the tin amount in the polymer could be demonstrated. Hence the functional SnMe3 groups can act as traps, a tin amount higher than 0.6 % can negatively influence the mobility. Alternatively the alternated TIPS-BDT/Fluoren-copolymer P-5-Stille is polymerized by the Suzuki-Method. The highest mobility of 10-2 cm2/Vs is obtained with P-5-Suzuki as active semiconductor layer in OFET. In comparison to P-5-Stille this mobility is two orders of magnitude higher, because in P-5-Suzuki traps are minimized and the charge transfer is improved. The synthesis of homopolymer P-12 as well as the copolymer with aromatic benzothiadiazole P-9 resulted in insoluble polymers. For this reason terpolymers containing TIPS-BDT/Fluoren/BTD units are designed. Additionally an attempt has been made to introduce the TIPS-BDT unit in the side chain of styrene. The introduction of BTD in the conjugated main chain influences especially the absorption and electrochemical properties. Compared to TIPS-BDT/Fluoren-copolymer the absorption of the terpolymer is shifted to the visible region and the LUMO values decreased. An improvement in the device performance is not observed. A side chain polystyrene containing TIPS-BDT P-13 is synthesized successfully. The amorphous and soluble P-13 showed comparable mobilities (µ = 10-5 cm2/Vs) as known styrene based polymers. A further aim of this work is the synthesis of organo-soluble benzodithiophene based small molecules. Using Suzuki- and Stille-reactions different aromatic cores as endcappers are connected by σ-bonds at the 2,6-position of TIPS-BDT. UV/VIS-measurements show a red-shift of the absorption maxima with extension of the π-conjugated system. Furthermore it is possible to introduce thermal cross linkable allyloxy-groups. The F-atoms in the molecule lead to stronger intermolecular interactions in the solid state, which improves the electronic properties and lead to high mobilities up to 0.09 cm2/Vs for TIPS-BDT (SM-4).