Porous solids are a class of materials of high scientific and technological significance. Indeed, they have the ability to interact with atoms, ions or molecules not only at their surface but also throughout the bulk of the solid. This ability places these materials as a major class involved in many applications such as gas storage and separation, catalysis, drug delivery and sensor technology. Metal-Organic Materials (MOMs) or coordination polymers (CPs) are crystalline compounds constructed from metal ions or clusters and organic components that are linked via coordination bonds to form zero-, one-, two or three-periodic structures. Porous Metal-Organic Materials (MOMs) or Metal-Organic Frameworks (MOFs) are a relatively new class of nanoporous materials that typically possess regular micropores stable upon removal of guests. An extraordinary academic and industrial interests was witnessed over the past two decades and is evidenced by a fantastic grow of these new materials. Indeed, due to a self-assembly process and readily available metals and organic linkers, an almost infinite number of materials can, in principle, be synthesized. However, a rational design is very challenging but not impossible. In theory, MOMs could be designed and synthesized with tuned functionalities toward specific properties that will determine their potential applications. The present research involves the design and synthesis of functional porous Metal-Organic Materials that can be used as platforms for specific studies related to many applications such as for example gas storage and particularly hydrogen storage. In this manuscript, I will discuss the studies performed on existing major Metal-Organic Frameworks, namely Zeolite-like Metal-Organic Frameworks (ZMOFs) that were designed and synthesized in my research group. My research was also focused on the design and the synthesis of new highly porous isoreticular materials based on Metal-Organic Polyhedra (MOP) where desirable functionality and unique features can be introduced in the final material prior and/or after the assembly process. The use of hetero-functional ligands for a rational design toward binary or ternary net will also be discussed in this dissertation.

Abstract: Metal-Organic Frameworks (MOFs) are a class of highly porous, hybrid, functional and crystalline extended coordination compounds. Their exceptional properties renders them ideal for a wide range of applications including gas storage and catalysis. Especially for catalysis, MOFs are receiving attention as well-defined supports for organometallic heterogeneous catalysis with noticeably the post-synthetic grafting of transition metal complexes on secondary building units (SBU) containing hydroxides moieties. The objective of this dissertation is to explore the synthesis, reactivity and functionalization of MOFs with SBU containing hydroxides units by transition metal catalyst using the Surface Organometallic Chemistry (SOMC) approach. Chapter 1, gives an introduction to the field of MOF and their applications to catalysis through the functionalization of hydroxide containing SBUs. This chapter introduces also the SOMC strategy with an overview of its catalytic application for olefin metathesis and CO2 conversion. Chapter 2 and 3 give a detailed application of SOMC to MOFs with the selective grafting of the W(≡CtBu)(CH2tBu)3 complex on the highly crystalline and mesoporous Zr-NU-1000 MOF. The obtained single site material, Zr-Nu-1000-W, is fully characterized using state of the art experimental methods and all the steps leading to the final grafted moieties were identified by DFT. Zr-NU-1000-W is active for olefin metathesis and is further fine-tuned by activation with EtAlCl2 giving a more selective and stable catalyst. Moreover, the nature of the grafted species could be modulated by pre-activation of the initial W(≡CtBu)(CH2tBu)3 complex with dmpe giving W(≡CtBu)(=CHtBu)(CH2tBu)(dmpe) also grafted on Zr-NU-1000. Chapter 4 and 5, describe the deliberate design and bulk synthesis of a new zirconium MOF, Zr-she-MOF-2, and highlight the discovery of a new highly connected MOF, RE-urx-MOF-1, based on a careful combination of rare earth (RE) metals with heterobifunctional triangular tetrazolate-based ligand. Additionally, the replacement of the tetrazolate functionality by carboxylate, leads to the formation of a different MOF structure RE-gea-MOF-4 having the gea topology with the presence of 18-connected nonanuclear RE cluster. Both Zr-she-MOF-2 and RE-gea-MOF-4 are active for the coupling of epoxides with CO2 to form cyclic carbonate in the presence of Bu4NBr. Finally, Chapter 6 will discuss the conclusions and perspectives of this dissertation.

[ES] Se han preparado varios materiales metal orgánicos de circonio MOF-808 para evaluar sus propiedades catalíticas en reacciones tipo Meerwein-Ponndorf-Verley (MPV) para la reducción de compuestos carbonílicos. En particular, se han sintetizado compuestos tipo MOF-808 modificados en los que una pequeña fracción de los ligandos trimesato presentes en el MOF original se ha reemplazado por ligandos dicarboxilato, como una estrategia para inducir la creación controlada de defectos estructurales. Los ligandos utilizados han sido: isoftalato (MOF-808-IPA), 3,5-piridindicarboxilato (MOF-808-Pydc), 5- aminoisoftalato (MOF-808-NH2) y 5-hidroxiisoftalato (MOF-808-OH). Todos los materiales obtenidos presentan una elevada cristalinidad y son isoreticulares respecto al MOF-808 original. Se ha evaluado la actividad catalítica del MOF-808 original y de los materiales modificados en reacciones tipo MPV, utilizando ciclohexanona como compuesto modelo. Todos los materiales presentan una elevada actividad catalítica, superior a la del tereftalato de circonio UiO-66 utilizado como referencia. Esta mayor actividad catalítica se corresponde a un mayor número de iones Zr4+ con insaturación coordinativa presentes en el MOF-808 con respecto al UiO-66. Además, los materiales MOF-808-IPA y MOF-808-Pydc presentan una mayor actividad que el MOF-808 original, lo que se debe a la presencia de centros activos menos congestionados estéricamente debido a la introducción de los ligandos dicarboxilato. Una ventaja adicional de compuestos MOF-808 con respecto al UiO-66 es su sistema de poros más grande, lo que permite la conversión de moléculas de mayor tamaño. Para evaluar esta característica, se ha utilizado un compuesto de gran tamaño, la estrona, capaz de penetrar en los poros del MOF-808 pero no en el UiO-66. En consecuencia, el MOF-808 es capaz de convertir por completo la estrona de forma selectiva a estradiol, mientras que el UiO-66 apenas presenta actividad. Además, cuando se usa el MOF-808 como catalizador, se produce una cantidad considerable del isómero 17alfa-estradiol, difícil de obtener por otros medios, por lo que las propiedades de diastereoselectividad del MOF-808 en reacciones MPV resultan de gran interés preparativo. Con el fin de estudiar en mayor detalle la diastereoselectividad de reacciones MPV catalizadas por MOF-808, se ha estudiado la reducción de ciclohexanonas substituidas: 3-metilciclohexanona (3MeCH), 2-metilciclohexanona (2MeCH) y 2-fenil-ciclohexanona (2PhCH). En función del alcohol utilizado como reductor y de la posición del grupo substituyente en la ciclohexanona, el MOF-808 favorece selectivamente la formación de uno u otro isómero, con una diastereoselectividad variable: 82%, 61% y 94%, respectivamente para 3MeCH, 2MeCH y 2PhCH. Es posible racionalizar estos resultados considerando la formación preferencial de uno u otro estado de transición en el espacio confinado disponible dentro de los poros del MOF. Las características energéticas del proceso se han analizado mediante el uso combinado de estudios cinéticos y cálculos teóricos. Finalmente, en vista las interesantes propiedades del MOF-808 como catalizador para reacciones MPV, se ha extendido con éxito el uso de este material a la preparación de compuestos hidroxiesteroides de difícil obtención y de interés farmacológico mediante la reducción quimio-, regioy diastereoselectiva del correspondiente oxoesteroide. De esta forma, se han conseguido obtener en un solo paso de reacción y con una elevada selectividad los siguientes compuestos: 17alfa-estradiol, 5alfa- androstan-3beta,17alfa-diol y epitestosterona, lo que demuestra el potencial del MOF-808 como catalizador para la síntesis de compuestos de alto valor añadido. / [CA] S'han preparat varis materials metall orgànics de zirconi MOF-808 per avaluar les seves propietats catalítiques en reaccions tipus Meerwein-Ponndorf-Verley (MPV) per a la reducció de composts carbonílics. En particular, s'han sintetitzat composts tipus MOF-808 modificats en els que una petita fracció dels lligands trimesat presents en el MOF original s'han reemplaçat per lligands dicarboxilats, com una estratègia per induir la creació controlada de defectes estructurals. Els lligands utilitzats han sigut: isoftalat (MOF-808-IPA), 3,5-piridindicarboxilat (MOF-808-Pydc), 5-aminoisoftlatat (MOF-808- NH2) i 5-hidroxiisoftalat (MOF-808-OH). Tots els materials preparats presenten una elevada cristal·linitat i són isoreticular respecte al MOF-808 original. S'ha avaluat l'activitat catalític del MOF-808 original i dels materials modificats en reaccions tipus MPV, utilitzant ciclohexanona com a compost model. Tots els materials presenten una elevada activitat catalítica, superior a la del tereftalat de zirconi UiO-66 utilitzat com a referència. Aquesta major activitat catalítica es correspon a un major nombre d'ions Zr4+ amb insaturació coordinativa presents en el MOF-808 respecte a l'UiO-66. A més, els materials MOF-808-IPA i MOF-808-Pydc presenten una major activitat que el MOF-808 original, el que és debut a la presència de centres actius menys congestionats estèricament debut a la introducció dels lligands dicarboxilat. Un avantatge addicional dels MOF-808 respecte a l'UiO-66 és el seu sistema de porus més gran, que permet la conversió de molècules de major tamany. Per avaluar aquesta característica, s'ha utilitzat un compost de gran taman, l'estrona, capaç de penetrar en els porus del MOF-808 però no en els de l'UiO-66. En conseqüència, el MOF-808 és capaç de convertir completament l'estrona de forma sel·lectiva a l'estradiol, mentre que l'UiO-66 gairebé no presenta activitat catalítica. A més, quan s'usa el MOF- 808 com a catalitzador, es produeix una quantitat considerable de l'isòmer 17alfa-estradiol, difícil d'obtenir per altre medis, de manera que les propietats de diastereoselectivitat del MOF-808 en reaccions MPV resulten de gran interès preparatiu. Per tal d'estudiar en major detall la diastereoselectivitat de reaccions MPV catalitzades per MOF-808, s'ha estudiat la reducció de ciclohexanones substituïdes: 3-metilciclohexanona (3MeCH), 2- metilciclohexanona (2MeCH) i 2-fenil-ciclohexanona (2PhCH). En funció de l'alcohol usat com a reductor i de la posició del grup substituent en la ciclohexanona, el MOF-808 afavoreix selectivament la formació d'un o de l'altre isòmer, amb una diastereoselectivitat variable: 82%, 61% y 94%, respectivament per a 3MeCH, 2MeCH y 2PhCH. És possible racionalitzar aquest resultats considerant la formació preferent d'un o l'altre estat de transició en l'espai confinat disponible dins dels porus del MOF. Les característiques energètiques del procés s'han analitzat mitjançant l'ús combinat d'estudis cinètics i càlculs teòrics. Finalment, en vista de les interessants propietats del MOF-808 com a catalitzador per a reaccions MPV, s'ha estès amb èxit l'ús d'aquest material a la preparació de composts hidroxiesteroids de difícil obtenció i d'interès farmacològic mitjançant la reducció quimio-, regio- i diastereoselectiva del corresponent oxoesteroid. D'aquesta manera, s'ha aconseguit obtenir en un únic pas de reacció i amb una elevada selectivitat els següents composts: 17alfa-estradiol, 5alfa-androstan-3beta,17alfa-diol i epitestosterona, el que demostra el potencial del MOF-808 com a catalitzador per a la síntesi de composts d'alt valor afegit. / [EN] Various zirconium-containing MOF-808 compounds have been prepared as potential catalysts for the Meerwein-Ponndorf-Verley (MPV) reduction of carbonyl compounds. Modified MOF-808 have been synthethized in which a small fraction of the trimesate ligands present in pristine MOF-808 has been replaced by dicarboxylate ligands, as a strategy to induce a controlled creation of defects. The linkers used are: isophthalate (MOF-808-IPA), 3,5-pyridinedicarboxylate (MOF-808-Pydc), 5-aminoisophthalate (MOF-808-NH2) and 5-hydroxyisophthalate (MOF-808-OH). All these compounds are highly crystalline and isoreticular with pristine MOF-808. The catalytic activity of pristine and defect engineered MOF-808 has been evaluated for MPV reactions, using cyclohexanone as model substrate. All the materials show a higher catalytic activity than that of zirconium terephthalate UiO-66 used as reference. This higher activity is attributed to the higher amount of coordinatively unsaturated Zr4+ ions in MOF-808 than in UiO-66. Moreover, MOF- 808-IPA and MOF-808-Pydc are more active than pristine MOF-808, which is due to the creation of less sterically crowded sites due to the introduction of defective dicarboyxlate linkers. A further advantage of MOF-808 over UiO-66 is the presence of a wider pore system, which allows converting bulkier substrates. To evaluate this characteristic, a bulky ketone has been used; estrone, which can enter the pores of MOF-808 but not those of UiO-66. Accordingly, MOF-808 can fully convert estrone selectively to estradiol, while UiO-66 shows barely any catalytic activity. Interestingly, when MOF- 808 is used as catalysts, a noticeable amount of the isomer 17alpha-estradiol is produced, which is difficult to obtain by other means. Therefore, the diastereoselective properties of MOF-808 for MPV reactions are interesting from the preparative point of view. In order to investigate in more detail the diastereoselective properties of MOF-808 for MPV reactions, various substituted cyclohexanones have been considered: 3-methylcyclohexanone (3MeCH), 2- methylcyclohexanone (2MeCH) and 2-phenylcyclohexanone (2PhCH). Depending on the alcohol used as reducing agent and the position of the substituent in the cyclohexanone molecule, MOF-808 selectively favors the formation of one isomer or the other with a different diastereoselectivity: 82%, 61% and 94%, respectively for 3MeCH, 2MeCH y 2PhCH. These results can be rationalized by considering the preferential formation of a given transition state in the confined space available inside the MOF pores. The energetic characteristics of the process have been analyzed by a combined use of kinetic studies and theoretical calculations. Finally, in view of the interesting properties of MOF-808 as catalyst for MPV reactions, this material has been successfully applied to the preparation of a number of challenging hydroxysteroid compounds with pharmacologic interest through a chemo-, regio- and diastereoselective reduction of the corresponding oxosteroid. In this way, it has been possible to prepare in one single reaction step the following compounds: 17alpha-estradiol, 5alpha-androstan-3beta,17alpha-diol and epitestosterone. This demonstrates the high potential of MOF-808 as a catalysts for the synthesis of high added value compounds. / I want to thank the European Union’s Horizon 2020 research and innovation program for a contract under the Marie Sklodowska-Curie grant agreement No. 641887 (Project acronym: DEFNET). / Mautschke, H. (2019). Zirconium Metal Organic Frameworks as Heterogeneous Catalysts for Meerwein-Ponndorf-Verley Reactions [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/130203 / TESIS

Nanotechnology as a field has the potential to answer some of the major challenges that mankind faces in regards to environmental sustainability, energy generation and health care. Though, solutions to these concerns can not necessarily rely on our current knowhow. Instead, it is reasonable to expect that humanity must adapt and learn to develop new materials and methods to overcome the adversities that we are facing. This master thesis has involved developing novel materials, serving as a small step in the continuous march towards a bright future where this is possible. More specifically, this work sought to combine mesoporous magnesium carbonate with various metal-organic frameworks to utilize the beneficial aspects from each of these constituents. The ambition was that these could be joined to render combined micro-/mesoporous core-shell structures, with high surface areas and many active sites whilst maintaining a good permeability. Numerous different synthesis routes were developed and explored in the pursuit of viable routes to design novel materials with potential future applications within for instance drug delivery, water harvesting from air and gas adsorption. Coreshell structures of the hydrophilic mesoporous magnesium carbonate covered with the hydrophobic zeolitic imidazole framework ZIF-8 was successfully synthesized for the first time, and practical studies demonstrated a dramatically enhanced water stability, which is perceived to have an impact on further research on these materials. ZIF-67 was also combined with mesoporous magnesium carbonate in a similar manner. Further, Mg-MOF-74 was grown directly from mesoporous magnesium carbonate, where the latter acted as a partially self-sacrificing template, with the aim of rendering a porous hierarchical structure with contributions from the micro- and mesoporous ranges. The outcomes of all these syntheses were characterized using several analyzing methods such as scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and nitrogen sorption analysis.

Chromophore is a molecule or a part of a molecule which is responsible for its appearance color. This definition has been evolving over time with the progress of science. Contemporary scientific advances have expanded its meaning: to an inclusive level, chromophore is an irreducible collective of fundamental particles, which can represent the photophysical (optical physical) properties of the macroscopic matter. Previous studies have already found that the same molecule can have different photophysical properties under different condensed states. Therefore, it is straight forward to conclude that the definition of chromophore should take such extrinsic influencing interactions of this given molecule into consideration, thus simply taking the smallest unit such as a molecule is not accurate. A good example is quantum dots. Same species of quantum dots possess the identical smallest chemical unit but can emit very differently due to quantum confinement effect, thus defining the smallest unit as the chromophore is apparently fallacious. In solid polymeric compositions, the chemical unit or building blocks may differ from the spectroscopic unit depending on how these chemical units interacts within their ensemble to evolve new properties such as a new transition dipole. As thus, understanding the evolution of photophysical behaviors between the targeted unit and neighbors is of much importance to determine whether they should be considered as one chromophore or many. This requires a thorough understanding towards the evolution of photophysical properties of a collective, and the construction of such collective will need to pay extra attention to, as any structural factor could have changed some photophysical interactions of the collective. The introductory chapter discusses the material platform and fundamental photophysics investigated in this dissertation. Chromophore assembly (CA) as a sylloge of several classes of self-assembled materials, including metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), porous organic polymers (POPs). Among them, MOF-based CAs (MOF-CAs) featuring with the ease of synthesis, demonstrate incomparable promises to construct such collective with several appealing characteristics, including component diversity, chemical stability, structural porosity, and post-synthetic versatility (Chapter 1.1). As for here, the main target to achieve using these assemblies is to understand the interaction between adjacent chemical monomeric units, therefore their spatial arrangements are of the paramount importance. As modern theory discovered, both ordered and random systems can be very important for novel quantum material developments. Both crystalline and amorphous arrangements of monomeric units can be achieved by adopting different classes of materials. MOF-CAs could achieve the precise control of spatial arrangement including distance, direction, and dihedral angle by its crystalline structures, whereas porous organic polymer-based CAs (POP-CAs) could feature a total randomness. Photophysics, as the research topic targeting the firsthand knowledge gained by interrogating the information provided by the propagating light after its interaction with matters, could provide crucial knowledge of the targeted matter. Hence, photophysical properties could provide fundamental understanding of the targeted matter (Chapter 1.2). State-of-the-art spectroscopic methods and instrumentation have made it possible to critically examine new structures to correlate photophysics with the chemical structure of their assemblies. By combining multiple spectroscopic techniques along with theoretical study, several correlations between the electronic properties of the matter, such as structural features, have been investigated. To illustrate, some unique topology-dependent photophysical behaviors found in chromophore assemblies are introduced (Chapter 1.3). In this dissertation, the feasibility of using specific types of MOF-CAs to conduct unique photophysical studies has been carefully chosen and verified (Chapter 2). Next, with the help of first principles computations, the nature of several electronic excited states as a function of different extent of Van der Waals or electronic interaction in MOF-CAs is unveiled, and experimentally studied with several environmental variates (Chapter 3). The knowledge was then articulated to devise a strategy to improve resonance energy transfer process in MOF-CAs. Here, low electronic symmetry of linker and directionally aligned transition dipoles of their collective ensembled are found beneficial to improve such photophysical process in a bottom-up manner (Chapter 4). Then, a series of MOFs were rationally designed to examine the feasibility and extent of a nonlinear excitonic process, singlet fission, to promote the generation of carriers usable for many applications including light-harvesting applications. The outcome demonstrated MOF-CA is a powerful tool to design such materials and is more capable in terms of its tunability (Chapter 5). At last, a set of randomly oriented CAs in POP were examined for underlying excited state dynamic process that highlights a thermal activated delayed fluorescence (TADF) involving S1 and low-lying T2 excited states (Chapter 6). This dissertation has highlighted unique yet tunable excited-state features and photophysical processes within the well-defined molecular ensemble realized via porous frameworks. These photophysical properties differ from those of their respective molecular system in their solubilized forms. Studies in this dissertation demonstrates a reliable platform to investigate multibody chromophore systems and suggested several valuable discoveries and lights the way for the study of novel chromophore assembly systems.

No description available.

Les systèmes à délivrance de médicaments sont des technologies conçues pour administrer des molécules actives de façon optimisée afin d’améliorer leurs effets thérapeutiques tout en minimisant les effets secondaires. En effet, ces systèmes permettent une libération au niveau d’une cible thérapeutique. Les particules de type «cage» ont récemment attiré une attention particulière en raison de leur capacité accrue à (co)incorporer et à protéger des molécules actives vis-à-vis de dégradations in vivo. Les cyclodextrines (CDs) sont des exemples type de molécules "cage", possédant une cavité hydrophobe et une surface extérieure hydrophile. Nous avons élaboré tout d’abord des assemblages supramoléculaires à base de CDs d'environ 100 nm par une méthode douce consistant à mélanger deux solutions aqueuses de polymères neutres : 1) polymère de β-CD et 2) dextrane greffé avec la benzophénone, molécule invitée formant des complexes d’inclusion avec les CDs. La procédure de préparation « verte» en une seule étape rend la formulation attractive, malgré sa relativement faible capacité d’encapsulation (5%pds). Afin d'améliorer cete charge, nous avons élaboré des particules hybrides organiques-inorganiques (MOFs) à base de CDs. Avantageusement, les CD-MOF comportent non seulement des cavités de CD, mais aussi de larges pores engendrés lors l’auto-assemblage de CDs. Le lansoprazole a été incorporé avec succès (23%pds) dans les CD-MOFs et nous avons montré que chaque CDs était capable d’accueillir une molécule de principe actif. Cependant, l’inconvénient majeur des CD-MOFs est leur faible stabilité en milieu aqueux, limitant leur domaine d’application. Une modification de surface est apparue donc nécessaire pour améliorer leur stabilité. Notre stratégie a été d’incorporer les CD-MOFs dans des matrices d'acide polyacrylique (PAA). Des microsphères composites d’environ 650 nm ont été élaborées avec succès et ont permis une bonne stabilité et une libération prolongée sur plus de 48 h. Avantageusement, ces particules composites n’étaient pas toxiques in vitro même à des concentrations élevées. Ainsi, nous nous sommes orientés vers l’étude comparative de MOFs plus stables dans l’eau, à base de trimesate de fer. Les MIL-100 (Fe) (Material of Institute Lavoisier) figurent parmi les premiers MOF étudiés en tant que nanomédicaments (nanoMOFs). Ces particules, parfaitement stables dans l'eau, se dégradent dans des milieux contenant des phosphates en perdant rapidement leur caractère cristallin et leurs ligands constitutifs. De façon étonnante, nous avons constaté que malgré leur dégradation, ces MOFs conservent leur taille intacte. Une analyse approfondie basée sur la microscopie de Raman a permis d’obtenir des informations pertinentes sur la morphologie et la composition chimique de particules individuelles. Ainsi, il a été montré qu’un front d'érosion délimitait nettement un cœur intact et une coquillé inorganique érodée. Cependant, ni l’encapsulation ni la modification de surface des MOFs n’altérait leur intégrité. Enfin, nous avons étudié la co-encapsulation de deux molécules actives utilisées en combinaison (amoxicilline et clavulanate de potassium) dans les nanoMOFs stables à base de MIL-100 (Fe). Les antibiotiques ont été incorporées par imprégnation et chaque molécule s’est localisée préférentiellement dans un compartiment (large ou petite cage) corroborant parfaitement les simulations par modélisation moléculaire. De plus, il a été découvert, de manière surprenante, qu’un grand nombre de nanoMOFs se localisait au voisinage des bactéries (S.aureus) dans des cellules infectées. En se dégradant dans ces cellules, les nanoMOFs contenant les antibiotiques ont réduit de manière importante la charge bactérienne intracellulaire. Ces études révèlent le potentiel des particules de type «cage» pour une incorporation efficace de molécules actives et leur libération contrôlée et ouvrent de nombreuses possibilités d’application. / Drug delivery systems are engineered technologies to administer pharmaceutical ingredients to improve their therapeutic effects, aiming at minimizing their side effects by means of targeted delivery and/or controlled release. “Cage” particles recently drew special attention since they could act as “drug containers” which potentially load large amount of drugs, improve their stability and offer the possibilities to co-encapsulate synergetic drugs. Cyclodextrins (CDs) are typical “cage” molecules with a hydrophobic cavity and a hydrophilic outer surface. Taking advantage of the host-guest interactions between β-CD and benzophenone (Bz), CD based nanoparticles (CD-NPs) were the first formulation investigated. CD-NPs of around 100 nm were instantaneously produced by mixing two aqueous solutions of neutral polymers: 1) poly-CD containing β-CDs, and 2) Bz grafted Dex (Dex-Bz). The “green” and facile preparation procedure makes it attractive formulation, whereas its limitation lies on the low drug payloads (~ 5 wt%). In order to improve the drug loading capacity of CDs, porous CD based metal organic frameworks (CD-MOFs) were synthesized, which contain not only CD cavities, but also large pores built up by CDs self-assembly. Lansoprazole (LPZ) was incorporated in CD-MOF microcrystals (~ 6 µm) reaching payloads as high as 23.2 ± 2.1% (wt). Remarkably, each CD cavity was able to host a drug molecule, offering new opportunities for the use of CD-MOFs for drug delivery purposes. However, these particles disassembled in aqueous media, which limits their application for oral and intravenous administration. Surface modification is therefore necessary to improve their stability in water. The drug loaded CD-MOF nanocrystals (~ 650 nm) were successfully embedded in polyacrylic acid (PAA) polymer matrices. The composite microspheres exhibited spherical shapes and sustained drug release over a prolonged period of time (over 48 h). Drug loaded MOF/PAA composite microspheres were not toxic in vitro (cell viability ~ 90%) even at very high concentrations up to 17.5 mg/mL. MOF/PAA composite microspheres constitute an efficient and pharmaceutically acceptable MOF-based carrier for sustained drug release. However, the process of surface modification was complicated and lead to larger particles and reduced drug payloads. Water-stable MOFs are a novel type of hybrid particles, showing a high potential as drug carriers. Iron trimesate MOFs, namely, MIL-100 (Fe) (MIL stands for Material of Institute Lavoisier) was among the first nano-scaled MOFs used for drug delivery. These particles were stable in water but degraded in phosphate buffer saline (PBS) losing their crystallinity and constitutive trimesate linkers. However, it was discovered that they kept their morphology intact. A thorough analysis based on Raman microscopy was carried on to gain insights on both the morphology and chemical composition of individual particles. It was evidenced the formation of a sharp erosion front during particle degradation. Noteworthy, the MOFs did not degrade during drug loading nor surface modification. Co-encapsulation of two synergic antibiotics (amoxicillin and potassium clavulanate) in MIL-100 (Fe) nanoMOFs was achieved following a “green” procedure by soaking nanoMOFs in aqueous solutions of both drugs. Molecular modelling showed that each drug preferentially located in a separate nanoMOF compartment. Surprisingly, nanoMOFs were prone to co-localize with bacteria once internalized in infected macrophages. NanoMOFs acted synergistically with the entrapped drugs to kill intracellular S. aureus, in vitro. These results pave the way towards the design of engineered nanocarriers in which each component synergistically plays a role in fighting the disease. These studies unravel the potential of “cage” particles for efficient drug entrapment and controlled release and open numerous possibilities for applications.

Dans ce travail, nous étudions les conditions de synthèse pour la croissance directe des MOF Fe3 + / H2BDC et Fe3 + / H2NDC sur des surfaces de silicium fonctionnalisées (111) présentant une structure bien définie et dont la chimie de surface peut être adaptée pour favoriser / diriger la nucléation et la croissance hétérogènes Des MOF. Le mécanisme de croissance des MOF pertinents aux conditions choisies et les propriétés flexibles des cadres MIL-88B et MIL-88C sont également présentés avec l'aide des résultats du traitement post-synthèse.En ce qui concerne le système de morphologies et structures Fe3 + / H2BDC, les structures des couches obtenues dépendent fortement de la chimie de surface des monocouches greffées et aussi des conditions de synthèse (température, composition de la solution et temps de réaction). Les cristaux MIL-88B orientés sur la direction [001] sont seulement observés sur des surfaces fonctionnalisées par COOH et se sont révélés être favorisés en présence d'un excès de ligand en solution. La formation de la phase MIL-101 texturée le long de la direction [111] sur les surfaces de Si pyridyl et hydroxy-terminé est observée indépendamment de la condition de synthèse. Des cristaux MIL-101 isolés avec une orientation préférée le long de la direction [111] ont également été trouvés sur une surface terminée par acide à un excès de métal, alors que les îlots MIL-101 orientés au hasard sont observés au rapport R ≧ 1. Au contraire, aucune croissance du film ne s'est produite sur les surfaces de Si à terminaison méthyle. L'introduction de HCl, de H2O et de base faible organique -triéthylamine dans les solutions précurseurs affecte également la formation de films MOF avec différentes morphologies et couverture entre MIL-101 et MIL-88B sur des surfaces de Si à terminaison carboxylique. La dépendance temporelle de la croissance du film à un excès de ligand (R = 2) et d'un excès de métal (R = 0,5) sans et avec addition de HCl indique clairement que les deux MIL-88B et MIL-101 suivent un mode de croissance Volmer-Weber, Au cours de laquelle, des cristaux ou des grappes tridimensionnels isolés se sont formés à l'étape initiale et se sont développés latéralement et verticalement à la surface.En ce qui concerne le système de Fe3 + / H2NDC, en fonction des conditions de synthèse, y compris la température, le rapport du ligand à la concentration [Fe3 +] et [Fe3 +] seulement une phase-MIL-88C avec une couverture de surface variable allant des cristaux hexagonaux séparés aux couches composées d'isolés On a observé des faisceaux de cristallites hexagonales tous avec une orientation préférentielle le long de la direction. L'évolution des cristaux de MIL-88C avec le temps de cristallisation suggère également un mode Volmer-Weber.Les mesures ex-situ XRD du post-traitement vers les couches synthétisées constituées de MIL-88B et MIL-88C démontrent respectivement leur flexibilité lors de la désorption des molécules. Les mesures provisoires de la XRD in situ montrent également la réversibilité du cadre MIL-88C lors de l'absorption et de la libération de l'éthanol. / Within this work we investigate synthesis conditions for the direct growth of Fe3+/H2BDC and Fe3+/H2NDC MOFs onto functionalized silicon (111) surfaces exhibiting well-defined structure and whose surface chemistry can be tailored in order to favor/direct the heterogeneous nucleation and growth of the MOFs. Growth mechanism of relevant MOFs at chosen conditions and flexible properties of MIL-88B and MIL-88C frameworks are presented as well with the assistance of post-synthesis treatment results.Regarding the system of Fe3+/H2BDC morphologies and structures of obtained layers strongly depend both on surface chemistry of grafted monolayers and also on the synthesis conditions (temperature, solution composition and reaction time). Oriented MIL-88B crystals along [001] direction is only observed onto COOH-functionalized surfaces and was found to be favored in presence of ligand excess in solution. The formation of textured MIL-101 phase along [111] direction on pyridyl and hydroxyl terminated Si surfaces is observed irrespective of the synthesis condition. Isolated MIL-101crystals with preferred orientation along [111] direction was also found on acid terminated surface at excess of metal, whereas randomly oriented MIL-101 islands are observed at ratio R≧1. In contrary, no film growth happened on methyl terminated Si surfaces. Introduction of HCl, H2O and organic weak base-triethylamine into the precursor solutions also affects the formation of MOF films with various morphologies and coverage between MIL-101 and MIL-88B on carboxylic terminated Si surfaces. Time dependence of film growth at excess of ligand (R=2) and at excess of metal (R=0.5) without and with addition of HCl indicates clearly that both of MIL-88B and MIL-101 follows a Volmer-Weber growth mode, during which, isolated three-dimensional crystals or clusters formed at initial stage and grew both laterally and vertically on the surface.As to the system of Fe3+/H2NDC, depending on the synthesis conditions including temperature, ratio of ligand to [Fe3+] and [Fe3+] concentration only one phase-MIL-88C with variable surface coverage ranging from separated hexagonal crystals to layers composed of isolated bundles of hexagonal crystallites all with preferential orientation along [001] direction was observed. Evolution of MIL-88C crystals along with crystallization time also suggests a Volmer-Weber mode.Ex-situ XRD measurements of post-treatment towards the as-synthesized layers comprised of MIL-88B and MIL-88C respectively demonstrate their flexibility during molecule desorption. Tentative in-situ XRD measurements also show the reversibility of MIL-88C framework upon ethanol uptake and release.

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