En vue de vectoriser de façon ciblée des microcapsules de parfum vers un substrat textile pour des applications lessivielles, ce travail de thèse s’est consacré à la modification chimique de la surface de ces microcapsules en milieu aqueux par des polysaccharides ayant des affinités particulières pour les substrats de cellulose (agent d’aide au dépôt). Pour ce faire, une approche mettant en jeu des fonctionnalités époxy a été développée en deux étapes : fonctionnalisation de la surface des microcapsules par des molécules relais, puis greffage covalent d’un polysaccharide via la fonctionnalité époxy. Après chaque étape de greffage covalent en surface des microcapsules, différentes stratégies de caractérisations ont été mises en place (spectroscopies infrarouge, RAMAN, RMN du solide, XPS, ATG, mesure du potentiel zêta, gravimétrie, microscopie optique et fluorescente). Des expériences témoins ont également été réalisées pour prouver la non-adsorption des greffons de surface sur les microcapsules. La synthèse et le greffage de polysaccharides marqués avec des sondes fluorescente, alcyne et méthacrylate nous ont également permis d’appuyer nos conclusions. Afin d’envisager des modifications chimiques en milieu aqueux, la stabilité des composés époxy dans l’eau a dû être étudiée de façon précise par spectroscopie RMN en solution et nous avons abouti avec succès à une meilleure compréhension des phénomènes réactionnels époxy-amine et époxy-hydroxyle en milieu aqueux.Enfin, une enzyme (la lipase) a également pu être greffée de façon covalente via la fonctionnalisation époxy tout en conservant son activité catalytique. / Colloidal suspensions are of paramount significance in industrial applications. They are employed in various domains like paintings, inks, pigments, pharmacology, cosmetics, food,textile, composite materials or waste water treatment. Properties of colloids strongly depend on parameters such as the chemical composition, dimensions or morphology. To confer additional features to the colloids, i.e. stability, compatibilization, targeting, stealth properties and so on, it is also crucial to tailor their surface functionalization. In this work, we intend to develop a methodology allowing for tuning the surface properties of highly cross-linked fragrance microcapsules to graft polysaccharides. To do so, the first objective of this work is to identify functionalities at the surface (of the colloids) amenable to post-modifications. Based on this crucial insight, suitable surface chemistries are further explored to impart new properties to the colloids. Thus the presence of amine functions is highlighted by ninhydrine tests and then exploited to incorporate new functionalities at the surface of colloids.Incorporation of fluorescent tags (such as  Rhodamine Isothiocyanate, RITC), intermediate polymer epoxy chains (α,ω-epoxy functionalized polyethylene glycol or PGMA) are performed. Depending on the nature of the moieties to be grafted, the resulting colloids are subsequently characterized by Confocal Laser Scanning Microscopy (CLSM), FTIR, XPS, and RAMAN Spectroscopy. After this first step of functionnalization, epoxy rings at the surface are used to postgraft polysaccharides.

Ce manuscrit présente une méthodologie rationnelle de synthèse, caractérisation, détermination de la structure électronique et du comportement dynamique d’espèces bimétalliques électroniquement insaturées de type Cr(0)-M (avec M = Pd(II), Pt(II) ou Rh(I)). Ces nouvelles espèces constituent de rares exemples d’entités électro-insaturées à 14 électrons ayant la spécificité d’être persistantes en solution. Leur cohésion structurale provient essentiellement de la compensation d’un faible caractère de type donneur/accepteur entre les deux métaux par des interactions non-covalentes Coulombiennes. Nous montrons ainsi qu’en tirant profit du caractère ambiphile d’un ligand hétéroditopique capable de chélater un centre métallique par l’établissement d’une liaison covalente et d’une interaction non-covalente, de nouvelles espèces coordinativement insaturées peuvent être obtenues. Nous proposons d’appeler ce nouveau mode de chelation : « Hemichelation ». / The present manuscript will present a rational method of synthesis, characterization, determination of the electronic structure and dynamic behaviour of solution-persistent, and formally unsaturated binuclear Cr(0)-M complexes (with M= Pd(II), Pt(II) or Rh(I)). This new class of complexes constitutes rare examples of persistent coordinatively unsaturated 14-electrons complexes, whose cohesion stems essentially from a compensation of insufficient donor/acceptor Cr-M bonding by non-covalent interactions of preponderant attractive Coulombic nature. By taking advantage of the ambiphilic character of a heteroditopic ligand capable of chelating a metal centre through covalent and noncovalent bonds, truly coordination-unsaturated complexes can be synthesized in a manageable form. We propose to name “Hemichelation” the half-covalent/half noncovalent bonding-relationship between the ambiphilic heteroditopic ligand and the electron-unsaturated metallic centre.

Growing concerns regarding chemical weapons and toxic chemicals require the development and testing of robust materials and methods to capture and destroy these harmful chemicals. This dissertation discusses the fundamental properties (e.g., structure, stability and activity) of metal oxyhydroxide based 3-dimensional porous materials, such as metal organic frameworks (MOFs), and covalent organic frameworks (COFs), and their applications for gas capture and degradation, especially for toxic gases and chemical warfare agent simulants. We report and verify that the active sites in UiO-67 MOFs are the metal nodes (oxyhydroxides) and developed a paradigm which correlates the activities of the MOFs, the metal oxyhydroxides and their precursors. This new understanding can help researchers choose the optimum metal for the intended applications by avoiding the tedious and time-consuming procedures of MOF synthesis and purification. In addition, to characterize and understand the structures of active sites in UiO-67 MOFs, temperature programmed desorption mass spectrometry (TPD-MS) and in situ Fourier-transform infrared (FTIR) spectroscopy were performed under ultra-high vacuum (UHV) and revealed unconventional binding sites and assisted in the successful characterization of missing linker defects. Here, our research helped in identification of a new class of binding sites, via NH-π interactions, in UiO-67 MOFs will assist researchers working in the areas of gas storage/release in developing better materials. This study should facilitate the structural understanding of MOFs, their important attributes such as defects and their chemistry in the presence of toxic gases. After successful identification of active species in MOFs, with the ultimate goal of isolating andii depositing the active sites on porous carbonaceous materials, e.g., COFs, we have engineered a facile technique to synthesize robust nanoparticle-COF and evaluated the reasons for its improved catalytic properties over other materials. The discoveries and their implications discussed in this thesis address fundamental knowledge gaps and should aid the rational design of superior materials for in operando applications. / Chemistry

While conducting pilot studies into the usefulness of fusion to TELSAM polymers as a potential protein crystallization strategy, we observed novel properties in crystals of two TELSAM–target protein fusions, as follows. (i) A TELSAM–target protein fusion can crystallize more rapidly and with greater propensity than the same target protein alone. (ii) TELSAM–target protein fusions can be crystallized at low protein concentrations. This unprecedented observation suggests a route to crystallize proteins that can only be produced in microgram amounts. (iii) The TELSAM polymers themselves need not directly contact one another in the crystal lattice in order to form well-diffracting crystals. This novel observation is important because it suggests that TELSAM may be able to crystallize target proteins too large to allow direct inter-polymer contacts. (iv) Flexible TELSAM–target protein linkers can allow target proteins to find productive binding modes against the TELSAM polymer. (v) TELSAM polymers can adjust their helical rise to allow fused target proteins to make productive crystal contacts. (vi). Fusion to TELSAM polymers can stabilize weak inter-target protein crystal contacts. We report features of these TELSAM–target protein crystal structures and outline future work needed to validate TELSAM as a crystallization chaperone and determine best practices for its use.

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Rechargeable aqueous Zn-ion energy storage devices are promising candidates for next-generation energy storage technologies. However, the lack of highly reversible Zn2+-storage anode materials with low potential windows remains a primary concern. Here, we report a two-dimensional polyarylimide covalent organic framework (PI-COF) anode with high-kinetics Zn2+-storage capability. The well-organized pore channels of PI-COF allow the high accessibility of the build-in redox-active carbonyl groups and efficient ion diffusion with a low energy barrier. The constructed PI-COF anode exhibits a specific capacity (332 C g–1 or 92 mAh g–1 at 0.7 A g–1), a high rate capability (79.8% at 7 A g–1), and a long cycle life (85% over 4000 cycles). In situ Raman investigation and first-principle calculations clarify the two-step Zn2+-storage mechanism, in which imide carbonyl groups reversibly form negatively charged enolates. Dendrite-free full Zn-ion devices are fabricated by coupling PI-COF anodes with MnO2 cathodes, delivering excellent energy densities (23.9 ∼ 66.5 Wh kg–1) and supercapacitor-level power densities (133 ∼ 4782 W kg–1). This study demonstrates the feasibility of covalent organic framework as Zn2+-storage anodes and shows a promising prospect for constructing reliable aqueous energy storage devices.

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

La cristallisation est un phénomène dans lequel les atomes ou molécules s’arrangent de manière hautement ordonnée. Il s’agit d’une des plus anciennes méthodes de purification. De plus, la structure cristalline d’un matériau influence ses propriétés. En métallurgie, par exemple, plusieurs opérations sont effectuées sur le métal, chacune affectant la structure cristalline et par le fait même les propriétés du matériau. Une compréhension des facteurs affectant la structure cristalline serait désirable en chimie des matériaux. Par exemple, dans le développement de matériaux poreux, la structure permettrait de moduler la quantité de vide dans un cristal et d’ajuster ainsi sa porosité. Prévoir l’organisation moléculaire est aussi désirable dans les panneaux solaires afin de bien positionner les composantes actives. Pour les polymères, le taux de cristallinité affecte directement les propriétés mécaniques telles que la densité et la dureté. La cristallisation se fait par étape. Au début, quelques particules commencent par se lier intermoléculairement de manière réversible. À ce moment de la cristallisation, la perte d’entropie contrebalance les bénéfices enthalpiques et le processus n’est pas favorisé thermodynamiquement. Une fois qu’un certain nombre de particules se sont lié, un noyau ou germe de nucléation est formé et à ce moment la cristallisation devient favorisée thermodynamiquement. Cette étape critique s’appelle la nucléation. La structure et la forme du noyau de nucléation servent de gabarit pour la construction subséquente du cristal. Après la germination vient la croissance épitaxiale. Comprendre l’étape de germination permet donc de moduler l’organisation moléculaire au tout début de la formation du cristal. Le projet présenté dans ce mémoire vise à examiner le phénomène de la nucléation à l’aide de molécules organiques conçues pour porter plusieurs groupements pouvant se lier réversiblement de manière covalente. Le nombre critique de molécules pour construire un noyau de cristallisation et la nature de leur association peuvent être étudiés. Le cœur organique choisi pour ces molécules est celui de l’adamantane car ses dérivés cristallisent bien en général et peuvent être fonctionnalisés facilement. Le groupement choisi pour pouvoir se lier réversiblement est le nitroso, qui s’associe pour générer des liaisons azodioxy. L’objectif du projet fut donc la synthèse et l’étude du comportement du mono-, di-, tri- et tétranitrosoadamantane. / Crystallization is a phenomenon in which atoms or molecules arrange themselves in a highly ordered fashion. It is one of the oldest methods of purification. In addition, the structure of a crystalline substance influences its properties. In metallurgy, for example, many operations are applied to metals in an effort to change the crystal structure and thus the properties of the material. Acquiring a full comprehension of the factors affecting crystallization is therefore a desirable goal in materials chemistry. In the area of porous solids, for example, modifying the structure can be used to modulate the amount of free space inside the solid. Similarly, controlling the molecular organization of the components of solar panels is needed to optimize performance. For polymers, the degree of crystallinity directly affects mechanical properties such as density and hardness. Molecular crystallization is a stepwise process. At the start, a few molecules associate reversibly. At this point, the loss of entropy counterbalances stabilizing enthalpic effects, and the process is not favored thermodynamically. Once a certain number of molecules have assembled, a seed or germ of nucleation is formed. It is at this moment that crystallization becomes spontaneous. This critical step is called nucleation. The structure and shape of the seed serves as a template for subsequent construction of the crystal. After the seed is formed, the crystal then undergoes epitaxial growth. Understanding the seeding step allows modulation of the crystal at the very beginning of its formation. The project described in the present Master’s thesis aims to study the phenomenon of nucleation using specially designed organic molecules. The idea is to use molecules comprising multiple groups that can associate reversibly by forming weak covalent bonds. The critical number of molecules needed to obtain a crystal nucleus and their manner of association can be studied. The organic core chosen is that of adamantane because its derivatives tend to crystallize well and functionalization is straightforward. The functional group chosen to favor strong but reversible association is nitroso, because nitroso compounds typically exist in equilibrium with azodioxy dimers. The objective of work summarized in the memoir is to synthesis, characterize, and examine the associative properties of mono-, di-, tri-, and tetranitrosoadamantane.