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Cyclodextrin-modified metal-organic framework nanoparticles for the efficient delivery of hydrophilic antiviral and anticancer drugs / vectorisation de médicaments hydrophiles antiretroviraux et anticancereux par des nanoparticules mésoporeuses hybrides (nanomof) à surface modifiéeAgostoni, Valentina 25 April 2013 (has links)
Les nanoMOFs – nanoparticles poreuses hybrides ont récemment été introduites dans le domaine de la vectorisation des médicaments afin de combiner les avantages de systèmes purement organiques ou inorganiques. Les nanoMOFs biodégradables et biocompatibles à base de trimesate de fer (MIL-100) ont été étudiées. Une méthode de synthèse «verte» a été développée et validée, ouvrant la voie à la production à grande échelle et à l’utilisation de ces matériaux pour des applications biologiques. Par la suite, les MIL-100 nanoMOFs ont été proposées comme potentiels vecteurs pour l’administration de médicaments hydrophiles antirétroviraux et anti-cancéreux, tels que les analogues nucléosidiques azydothimidines mono et triphosphates ou encore le Topotécan. Finalement, une nouvelle stratégie de modification de surface des nanoMOFs par leur recouvrement avec une couronne à base de dérivés de la β cyclodextrine, a été developpée. / Hybrid porous materials, as Metal Organic Frameworks (MOF) have been recently introduced in the drug delivery field in the attempt to combine advantages of the conventional “purely organic” or “purely inorganic” nanocarriers, such as important loading capability and controlled release.In this work the potential of biodegradable and biocompatible MOF nanoparticles made of iron trimesate (MIL-100 nanoMOF) has been investigated. A “green” synthetic procedure has been developed and validated, opening the way to the scale up synthesis of these materials for biological applications. MIL-100 nanoMOFs have been further applied to the delivery of hydrophilic drugs such as antiretroviral nucleoside analogues mono and triphosphate (azydothimidine mono and triphosphate) and the anticancer drug topotecan. Finally a new method of nanoMOFs surface modification, based on the nanoparticles coating with a β cyclodextrin-based extrenall shell, has been developed
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Polímeros de coordenação à base de cobalto(II) e N,N'-bis(4-piridil)-1,4,5,8-naftaleno diimida como ligante e suas propriedade estruturais, espectroscópicas e fotoelétricas / Coordination polymers based on cobalt(II) and N,N\'-bis(4-pyridyl)-1,4,5,8-naphthalene diimide as ligand and their structural, spectroscopic and electronic propertiesCastaldelli, Evandro 05 February 2016 (has links)
Polímeros de coordenação têm atraído a atenção de pesquisadores na última década por conta de sua incrível versatilidade e virtualmente infinito número de possibilidades de combinação de ligantes orgânicos e centros metálicos. Estes compostos normalmente herdam as características magnéticas, eletrônicas e espectroscópicas de seus componentes base. Entretanto, apesar do crescente número de trabalhos na área, ainda são raros os polímeros de coordenação que apresentem condutividade elétrica. Para este fim, utilizou-se a N,N\'-bis(4-piridil)-1,4,5,8-naftaleno diimida, ou NDI-py, que pertence a uma classe de compostos rígidos, planares, quimicamente e termicamente estáveis e que já foram extensamente estudados por suas propriedades fotoeletroquímicas e semicondução do tipo n. O primeiro polímero de coordenação sintetizado, MOF-CoNDI-py-1, indicou ser um polímero linear, de estrutura 1D. O segundo, MOF-CoNDI-py-2, que conta com ácido tereftálico como ligante suporte, é um sólido cristalino com cela unitária monoclínica pertencente ao grupo espacial C2/c, determinado por difração de raios-X de monocristal. A rede apresenta um arranjo trinuclear de íons Co(II) alto spin com coordenados em uma geometria de octaedro distorcido, enquanto os ligantes NDI-py se encontram em um arranjo paralelo na estrutura, em distâncias apropriadas para transferência eletrônica. Com o auxílio de cálculo teóricos a nível de DFT, foi realizado um estudo aprofundado dos espectros eletrônicos e vibracionais, com atribuição das transições observadas, tanto para o MOF-CoNDI-py-2 quanto para o ligante NDI-py livre. A rede de coordenação absorve em toda a região do espectro eletrônico analisada, de 200 nm a 2500 nm, além de apresentar luminescência com característica do ligante. Dispositivos eletrônicos fabricados com um cristal do MOF-CoNDI-py-2 revelaram condutividades da ordem de 7,9 10-3 S cm -1, a maior já observada para um MOF. Além de elevada, a condutividade elétrica dos cristais demonstrou-se altamente anisotrópica, sendo significativamente menos condutor em algumas direções. Os perfis de corrente versus voltagem foram analisados em termos de mecanismos de condutividade, sendo melhores descritos por um mecanismo limitado pelo eletrodo to tipo Space-Charge Limited Current, concordando com a proposta de condutividade através dos planos de NDI-py na rede. A condutividade dos cristais também é fortemente dependente de luz, apresentando fotocondução quando irradiado por um laser vermelho, de 632 nm, enquanto apresenta um comportamento fotorresistivo frente a uma fonte de luz branca. Estes resultados, combinados, trazem um MOF em uma estrutura incomum e com elevada condutividade elétrica, modulada por luz, em medidas diretas de corrente. Não existem exemplos conhecidos de MOFs na literatura com estas características. / Coordination polymers have been a major topic in materials science during the past decade, thanks to their versatility and virtually infinite possible combinations between metal centers and organic ligands. These coordination polymers usually inherit the properties of their components, such as magnetic, spectroscopic and electronic characteristics. However, despite the increasing number of research papers in this topic, it is still hard to find coordination polymers featuring electronic conductivity. To achieve that, we used a naphthalene diimide derivative, N,N\'-bis(4-pyridyl)-1,4,5,8- naphthalene diimide or NDI-py, which belongs to a class of rigid, planar, thermally and chemically stable compounds, extensively studied due to their photoelectrochemical properties and their n-type semiconductivity. The first coordination polymer synthesised, MOF-CoNDI-py-1, was an amorphous linear polymer, with a 1D structure. Based on these observations, MOF-CoNDI-py-2 was synthesised by using terephthalic acid as a supporting ligand, and it is a crystalline solid which its monoclinic unit cell belongs to a C2/c space group, as determined by single crystal X-ray diffraction. This network features a trinuclear high-spin Co(II) unit, and each metal ion sits on a distorted octahedra coordination geometry, while the NDI-py ligands sit in a parallel arrangement, with distances suitable for electronic transfers. A detailed study of their vibrational and electronic spectra, supported by DFT calculations, was performed, as well as a full description and assignment of the observed bands. MOF-CoNDI-py-2 absorbs in the whole studied spectral region, from 200 nm to 2500 nm, while it also features a ligand-centered emission spectrum. Electronic devices built around its crystals revealed electric conductivities of 7.9 10 -3 S cm -1, which is, to the best of our knowledge, the highest for a MOF to this date. This conductivity is also highly anisotropic, being significantly less conductive in certain directions. The current versus voltage profiles were analysed in terms of known conduction mechanisms, with best fits when using an electrode-limited Space-Charge Limited Current mechanism, in agreement with the proposition that this conductivity happens through the NDI-py stacking planes. Additionally, this mechanism is influenced by an external light source, being a photoconductor with a red laser, 632 nm, and a photoresistor with a white light. Combined, these results bring a light-modulated, highly conductive MOF material with an unusual structure. As far as we know, there are no similar MOFs in the literature, which makes MOF-CoNDI-py-2 one of a kind.
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Potentiels des poly-hydroxyalcanoates (PHAs) bactériens pour l'encapsulation de molécules à visée thérapeutique / Potentials of bacterial Poly-HydroxyAlkanoates (PHA) for the encapsulation of therapeutic moleculesJain-Beuguel, Caroline 14 December 2018 (has links)
Les Poly(HydroxyAlcanoates) (PHA) sont des polymères naturels, biodégradables et biocompatibles, synthétisés par de nombreux organismes, et plus particulièrement des procaryotes. Il existe à ce jour plus de 150 types de monomères de PHA différents, accumulés chez différents genres bactériens, en tant que source d’énergie et de carbone. En effet, les granules de PHA intracellulaires sont produites en réponse à un apport en excès de sources de carbone dans l’environnement (glucides, acides gras…), couplé à une carence en éléments azotés nécessaires à la division cellulaire. De par leur caractère biodégradable et biocompatible, les PHA sont employés depuis plus de 20 ans comme biomatériaux dans les domaines pharmaceutiques et biomédicaux, notamment comme micro/nanovecteurs à visée thérapeutique. Ce doctorat met en évidence des méthodes de criblage moléculaire par PCR pour la sélection de bactéries productrices de PHA, isolées de sites hydrothermaux des océans Atlantique et Pacifique au cours de campagnes océanographiques Ifremer. Selon des protocoles de fermentation standardisés et optimisés, des polymères de poly(3-hydroxybutyrate-4-hydroxybutyrate) P(3HB4HB) d’intérêt biomédical ont été produits, puis des études taxonomiques et phylogénétiques ont été menées pour explorer la biodiversité microbienne associée aux environnements marins profonds. Ensuite, des PHA ont été modifiés par réaction thiol-ène photoactivée afin d’obtenir des copolymères hydrosolubles, adaptés pour l’enrobage de nanoparticules poreuses de type Metal-Organic Frameworks (MOF). La caractérisation physicochimique a été réalisée par différentes techniques, et notamment par SEM et STEM-EDX. Les systèmes hybrides poreux MOF-PHA ont ensuite été évalués quant à leur biocompatibilité vis-à-vis de cellules immunitaires (macrophages), par des tests de cytotoxicité et de prolifération cellulaire. Cette étude met en lumière les potentialités de cette nouvelle génération de nanovecteurs, synthétisés pour augmenter le bénéfice thérapeutique tout en minimisant les effets secondaires sur l’organisme humain. / Poly(HydroxyAlkanoates) (PHA) are natural polymers, biodegradable and biocompatible, synthesized by many organisms, especially prokaryotes. There are over 150 kinds of these polyesters, accumulated in a wide variety of bacteria as carbon and energy storage material. PHA granules are deposited intracellularly when microorganisms are cultivated in the presence of an excess of carbon source (glucids, fatty acids...) together with a nitrogenous nutrient deficiency. Due to their biodegradability and biocompatibility, PHA can be used as biomaterials in medical or pharmaceutical fields, and numerous therapeutic micro/nanovectors have already been developed over the past two decades.The present PhD research project highlighted molecular screening methods by PCR for the PHA producing Bacteria selection, isolated during Ifremer cruises from hydrothermal vents in Atlantic and Pacific oceans.According to standardized and optimized fermentation protocols, poly(3-hydroxybutyrate-4-hydroxybutyrate) P(3HB4HB) polymers of biomedical interest were produced, then taxonomic and phylogenetic studies were performed to explore microbial biodiversity associated with deep-sea environments. Next, PHA were modified by ‘click chemistry’ to obtain hydrosoluble copolymers, suitable for coating high porous Metal-Organic Frameworks (MOF) therapeutic nanoparticles. Physico-chemical characterization was performed using different techniques, and more particularly by SEM and STEM-EDX. MOF-PHA hybrid porous systems were then evaluated for their biocompatibility against immune cells (macrophages), by cytotoxicity and cellular proliferation tests. This study highlights potentials of these new generations of nanovectors, synthesized to increase the therapeutic benefit while minimizing side effects on the human body.
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Pendant Functional Groups in Metal-Organic Frameworks - Effects on Crystal Structure, Stability, and Gas Sorption PropertiesMakal, Trevor Arnold 03 October 2013 (has links)
The primary goal of this research concerns the synthesis and characterization of metal-organic frameworks (MOFs) grafted with pendant alkyl substituents to enhance stability and gas sorption properties for use in clean-energy related technologies. Initially, the focus of this work was on the synthesis and comparison of two isostructural MOFs built upon octahedral secondary building blocks; one with no alkyl substituents, and its dimethyl-substituted counterpart. The dimethyl-substituents are observed to enhance the stability of the framework, resulting in high Langmuir surface area (4859 m2 g-1) and hydrogen uptake capacity at 77 K and 1 bar (2.6 wt%).
In the second section, the length of pendant alkoxy substituents in semi-flexible MOFs was evaluated through the synthesis and characterization of two isostructural MOFs, one with dimethoxy (PCN-38) and one with diethoxy pendant groups (PCN-39). While PCN-38 exhibited moderate surface area and hydrogen uptake capacities, PCN-39 underwent structural change upon activation leading to a redistribution of pore sizes and selective adsorption of hydrogen over larger gases. This structural transformation is believed to originate from optimal space filling of the pendant groups.
In the third section, a series of NbO-type MOFs were synthesized with dimethoxy, diethoxy, dipropoxy, and dihexyloxy substituents and the relationship between chain length and framework stability identified. Increasing chain length was observed to increase moisture stability of the MOFs, resulting in a superhydrophobic material in the case of the dihexyloxy derivative. Thermal stability, however, decreased with increasing chain length, as evidenced from in situ synchrotron powder X-ray diffraction measurements (PXRD). This is in contrast to data obtained from thermogravimetric analysis and shows that the standard use of thermogravimetric analysis, which measures combustion temperatures, may not always provide an accurate description of the thermal stability of MOFs. The role of pendant groups in gas adsorption processes was evaluated through identification of side chains and guest species in the pores of MOFs through in situ synchrotron PXRD measurements.
In summary, three separate isostructural series of MOFs with various pendant groups have been discussed in this dissertation, with the roles of those pendant groups toward crystal structure, stability, and gas sorption properties analyzed.
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Polímeros de coordenação à base de cobalto(II) e N,N'-bis(4-piridil)-1,4,5,8-naftaleno diimida como ligante e suas propriedade estruturais, espectroscópicas e fotoelétricas / Coordination polymers based on cobalt(II) and N,N\'-bis(4-pyridyl)-1,4,5,8-naphthalene diimide as ligand and their structural, spectroscopic and electronic propertiesEvandro Castaldelli 05 February 2016 (has links)
Polímeros de coordenação têm atraído a atenção de pesquisadores na última década por conta de sua incrível versatilidade e virtualmente infinito número de possibilidades de combinação de ligantes orgânicos e centros metálicos. Estes compostos normalmente herdam as características magnéticas, eletrônicas e espectroscópicas de seus componentes base. Entretanto, apesar do crescente número de trabalhos na área, ainda são raros os polímeros de coordenação que apresentem condutividade elétrica. Para este fim, utilizou-se a N,N\'-bis(4-piridil)-1,4,5,8-naftaleno diimida, ou NDI-py, que pertence a uma classe de compostos rígidos, planares, quimicamente e termicamente estáveis e que já foram extensamente estudados por suas propriedades fotoeletroquímicas e semicondução do tipo n. O primeiro polímero de coordenação sintetizado, MOF-CoNDI-py-1, indicou ser um polímero linear, de estrutura 1D. O segundo, MOF-CoNDI-py-2, que conta com ácido tereftálico como ligante suporte, é um sólido cristalino com cela unitária monoclínica pertencente ao grupo espacial C2/c, determinado por difração de raios-X de monocristal. A rede apresenta um arranjo trinuclear de íons Co(II) alto spin com coordenados em uma geometria de octaedro distorcido, enquanto os ligantes NDI-py se encontram em um arranjo paralelo na estrutura, em distâncias apropriadas para transferência eletrônica. Com o auxílio de cálculo teóricos a nível de DFT, foi realizado um estudo aprofundado dos espectros eletrônicos e vibracionais, com atribuição das transições observadas, tanto para o MOF-CoNDI-py-2 quanto para o ligante NDI-py livre. A rede de coordenação absorve em toda a região do espectro eletrônico analisada, de 200 nm a 2500 nm, além de apresentar luminescência com característica do ligante. Dispositivos eletrônicos fabricados com um cristal do MOF-CoNDI-py-2 revelaram condutividades da ordem de 7,9 10-3 S cm -1, a maior já observada para um MOF. Além de elevada, a condutividade elétrica dos cristais demonstrou-se altamente anisotrópica, sendo significativamente menos condutor em algumas direções. Os perfis de corrente versus voltagem foram analisados em termos de mecanismos de condutividade, sendo melhores descritos por um mecanismo limitado pelo eletrodo to tipo Space-Charge Limited Current, concordando com a proposta de condutividade através dos planos de NDI-py na rede. A condutividade dos cristais também é fortemente dependente de luz, apresentando fotocondução quando irradiado por um laser vermelho, de 632 nm, enquanto apresenta um comportamento fotorresistivo frente a uma fonte de luz branca. Estes resultados, combinados, trazem um MOF em uma estrutura incomum e com elevada condutividade elétrica, modulada por luz, em medidas diretas de corrente. Não existem exemplos conhecidos de MOFs na literatura com estas características. / Coordination polymers have been a major topic in materials science during the past decade, thanks to their versatility and virtually infinite possible combinations between metal centers and organic ligands. These coordination polymers usually inherit the properties of their components, such as magnetic, spectroscopic and electronic characteristics. However, despite the increasing number of research papers in this topic, it is still hard to find coordination polymers featuring electronic conductivity. To achieve that, we used a naphthalene diimide derivative, N,N\'-bis(4-pyridyl)-1,4,5,8- naphthalene diimide or NDI-py, which belongs to a class of rigid, planar, thermally and chemically stable compounds, extensively studied due to their photoelectrochemical properties and their n-type semiconductivity. The first coordination polymer synthesised, MOF-CoNDI-py-1, was an amorphous linear polymer, with a 1D structure. Based on these observations, MOF-CoNDI-py-2 was synthesised by using terephthalic acid as a supporting ligand, and it is a crystalline solid which its monoclinic unit cell belongs to a C2/c space group, as determined by single crystal X-ray diffraction. This network features a trinuclear high-spin Co(II) unit, and each metal ion sits on a distorted octahedra coordination geometry, while the NDI-py ligands sit in a parallel arrangement, with distances suitable for electronic transfers. A detailed study of their vibrational and electronic spectra, supported by DFT calculations, was performed, as well as a full description and assignment of the observed bands. MOF-CoNDI-py-2 absorbs in the whole studied spectral region, from 200 nm to 2500 nm, while it also features a ligand-centered emission spectrum. Electronic devices built around its crystals revealed electric conductivities of 7.9 10 -3 S cm -1, which is, to the best of our knowledge, the highest for a MOF to this date. This conductivity is also highly anisotropic, being significantly less conductive in certain directions. The current versus voltage profiles were analysed in terms of known conduction mechanisms, with best fits when using an electrode-limited Space-Charge Limited Current mechanism, in agreement with the proposition that this conductivity happens through the NDI-py stacking planes. Additionally, this mechanism is influenced by an external light source, being a photoconductor with a red laser, 632 nm, and a photoresistor with a white light. Combined, these results bring a light-modulated, highly conductive MOF material with an unusual structure. As far as we know, there are no similar MOFs in the literature, which makes MOF-CoNDI-py-2 one of a kind.
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Metal Organic Frameworks (MOFs) and Porous Organic Polymers (POPs) for Heterogeneous Asymmetric CatalysisJi, Youngran 01 January 2015 (has links)
The administration of enantiopure drugs brings advantages such as improved efficacy, more predictable pharmacokinetics and reduced toxicity from the point of view of the pharmaceutical area.[1] For this reason, a tremendous amount of supply and demand for enantiomeric pure compounds has been shown not only in market, but industry and academia.[2-4] According to the industry publication Genetic Engineering and Biotechnology News (GEN) in 2014, 22 billion dollars were accounted for enantiopure form of drugs such as Sovaldi® (Sofosbuvir), Crestor® (Rosuvastatin), and Advair® (fluticasone/salmeterol).
The fact that one enantiomer can be pharmacologically effective whereas the other enantiomer can be inactive or display non-desirable activity, chiral resolution and asymmetric synthesis research has broken out in recent years to obtain one desired stereoisomer. Enormous amounts of well-organized and rationalized research results for higher enantiomeric selectivity and efficiency has been reported with diverse chiral ligands and transition metals in academia.[5-10] However novelty-driven results from academic area does not meet the requirement in industry field for the practical issue, especially tedious separation process that require high cost and effort. In addition, methodologies developed with privileged chiral ligands and transition metal complexes leave a concern like undesired residue of trace amount of toxic metals in the products.
In this dissertation, two types of heterogeneous asymmetric catalyst were investigated to find the alternative that accommodates industrial requirement to obtain enantiomeric pure compounds and novelty-driven academic demands. Firstly, constructions of rationally designed metal organic frameworks (MOFs) using chiral BINOL-derived phosphoric acid ligands were achieved. Overall, catalytic reactions with ocMOFs showed lower enatioselectivity than their homogeneous counterparts, but one of the MOFs, ocMOF-1, was found to exhibit improved enantioselectivity than its homogeneous counterpart in the context of transfer hydrogenation reaction of benzoxazine. Lower enatioselectivity with ocMOFs was rationalized by the chiral environment change by the formation of frameworks in a computational study.
In addition, self-supported heterogenization of chiral BINOL-phosphoric acid was achieved by the Yamamoto coupling reaction, and by using catalytically active ocPOP-1 having nanoscopic channels, enantioselectivity was obtained up to 48% in transfer hydrogenation of N-PMP ketimine. Although extension of substituent groups at 3, 3' positions was expected to bring enhanced steric hindrance and to influence to enantioselectivity positively, lack of spatially well-defined interactions induced by this chiral environment change might have lowered the enantiomeric selectivity of the catalytic reaction using ocPOP-1 than its counterpart.
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Using external factors to improve gas adsorption in nanoporous materials : control of humidity and mechanical pressure / Utilisation de paramètres externes pour améliorer l'adsorption de gaz dans les matériaux nanoporeux : contrôle de l'humidité et de la pression mécaniqueChanut, Nicolas 01 December 2016 (has links)
L'augmentation du niveau de CO2 atmosphérique est un sujet de préoccupation publique notoire. Afin d'atténuer son impact sur l'environnement, il est urgent de réduire les émissions de CO2 d’origines anthropiques. Une méthode considérée comme viable est la capture de CO2 par des procédés d’adsorption en utilisant une classe émergente de matériaux, les Metal-Organic Frameworks (MOFs). A ce jour, l’évaluation des MOFs s’est principalement axée sur leurs performances de séparation (capacité, sélectivité et régénération). Cependant, des facteurs externes peuvent influer sur les performances globales des procédés. L’objectif de cette thèse est d’évaluer trois d’entre eux : la présence de vapeur d’eau dans les effluents gazeux, l’effet de la mise en forme des matériaux et l’effet d’une pression mécanique externe sur les performances d’adsorption de gaz. Il est montré que ces facteurs externes peuvent être utilisés pour améliorer les performances des procédés dans des conditions spécifiques. / The increase in atmospheric CO2 level is a notorious matter of public concern. To mitigate its impact on the environment, it is urgent to reduce emissions of anthropogenic CO2. A method considered by many as a viable option is CO2 capture by adsorption using an emerging class of materials, the Metal-Organic Frameworks (MOFs). To date, evaluation of MOFs has been mainly focused on the separation performance of the material looking at the capacity, selectivity and regeneration capability. However external factors can influence the overall performances of processes turning to industrial applications. The purpose of this thesis was to evaluate three of them: the presence of water vapor in post-combustion flue gases, the effect of shaping powders into pellets form and the effect of an external mechanical pressure on gas adsorption performance. Unexpectedly, it is shown that these external factors could be used to improve process performances under specific conditions.
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Conception et fonctionnalisation de MOFs pour le greffage et l'encapsulation de complexe organométallique / Development of MOFs as supports or host for organometallic complexesLescouet, Tristan 14 December 2012 (has links)
Les Metal-Organic Frameworks résultent de l’organisation de clusters métalliques et demolécules organiques chélatantes qui forment un réseau cristallin poreux. Leur découverte apermis des avancées majeures dans le domaine du stockage et de la séparation des gaz.Malheureusement la faible stabilité et l’acidité modérée de ces matériaux ne les rendent quepeu compétitifs par rapport aux zéolites dans le domaine du raffinage ou de la dépollution. Ils’agit d’explorer, avec ces matériaux, de nouvelles applications catalytiques en tirant partie deleur principale qualité : leur modularité. En effet le large choix de métaux, de ligands, ainsique la post fonctionnalisation de ces derniers permet la synthèse contrôlée de matériauxpossédant des propriétés de flexibilité, de confinement ainsi qu’un environnement chimiquesimilaire à celui des sites actifs des enzymes. Ce travail s’inspire du procédé catalytique desenzymes pour obtenir des MOFs hautement sélectifs en conditions douces. Nous décrivons ledéveloppement de méthodes pour encapsuler des catalyseurs organométalliques dans despores calibrés afin de modifier la sélectivité d’une réaction d’oxydation et stabiliser lecatalyseur. Quatre MOFs supportant des groupes amino ont été synthétisés afin de permettreleur post fonctionnalisation. Les propriétés de flexibilité ainsi que la distribution des sitespotentiellement actifs du MOF MIL-53 ont également été contrôlés grâce à lafonctionnalisation partielle de la structure. Enfin ces amino MOFs furent post fonctionnalisésen isocyanate en deux étapes afin d’améliorer la réactivité de la structure et de permettre legreffage de diverses amines. Ces outils pourraient permettre à court terme la conception deMOFs dont les pores ont un environnement semblable aux metalloenzymes. / MOFs are generated from the association of metallic clusters connected by organic linkers toform crystalline porous materials. Their discovery was a breakthrough in the domain ofseparation and gas storage. Unfortunately, MOFs have a low stability and moderate acidityand cannot compete with zeolites for use in industrial catalysis. To design a viable MOFcatalyst, we can take advantage of its almost infinite possibility of customisation. Indeed, alarge choice of metal, linkers or post synthetic modifications allow the creation ofenvironments similar to the active sites of enzymes and can lead to the synthesis of solidswith analogue flexibility or “molecular recognition” properties. This work takes inspirationfrom enzymes to mimic their ability to catalyse reactions with high chemio-, region- andenantio-selectivity in mild conditions. We developed a method for the encapsulation oforganometallic complexes in the large pore of MOF MIL-101. The selectivity of an oxidationreaction was modified and the catalyst was stabilised within the MOF. In addition, four aminofunctionalized MOFs were synthesized as starting materials for post functionalization. Theirflexibility and the active site distribution were controlled by the use of a “mixed linker”strategy: functionalized linkers were diluted with unfunctionalized ones during the synthesis.Lastly, these amino-MOFs were post-functionalized in two steps in isocyanate in order toameliorate the structure reactivity and allow for the grafting of a large range of amines. Thiswork brings the tools for the synthesis of potential “artificial enzymes”.
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MOFs à surface modulable pour l’encapsulation et la libération de macromolécules / Engineered Surface Metal Organic Frameworks (MOFs) for Encapsulation and Delivery of MacromoleculesHidalgo Crespo, Tania 02 December 2015 (has links)
L'émergence d’un nouveau système nanoparticulé dans le domaine biomédical, les matériaux hybride poreux du type MOF (pour Metal Organic Framework), a récemment attiré beaucoup d'attention en raison de leur grande versatilité structurale et chimique. En particulaire, le trimésate de fer(III) mésoporeux (MIL-100; MIL pour Matériau de l'Institut Lavoisier) a démontré des capacités remarquables de stockage de médicaments avec leur libération contrôlée dans des conditions physiologiques, ainsi que des propriétés en imagerie très intéressantes.Néanmoins, avant toute bioapplication, il estnécessaire d’étudier leur toxicité et leur profile de biodistribution, lesquels sont fortement affectés par plusieurs facteurs (composition, dégradabilité, chimie de surface, etc.). Ainsi, l’objectif principal de ce travail de thèse porte sur l'évaluation de la biocompatibilité de MOFs nanométriques et leur passage de barrières physiologiquespar différentes voiesd'administration (en particulier, par voie intraveineuse, orale et cutanée) en fonction de leurs propriétés physico-chimiques. / The recent emergence of nanometric porous metal-organic frameworks (nanoMOFs) in the biomedical field has recently attracted a great deal of attention owing to their large porosity and versatile composition. Particularly attractive is the mesoporous iron(III) trimesate (MIL-100; MIL stands for Material of Institute Lavoisier), which has shown exceptional loading of challenging drugs, together with their controlled release under physiological conditions and interesting imaging properties. Nevertheless, prior to any bioapplication, it is crucial investigate its toxicity and biodistribution profile, which are strongly affected by multiple factors (e.g. composition, degradability, surface engineering, etc.). Thus, the aim of this PhD work focuses on the evaluation of the nanoMOF biocompatibility and their physiological barrier crossing from different administration routes (specifically intravenous, oral and cutaneous) as a function of their physicochemical properties.
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NMR spectroscopy in adsorption studies of metal-organic frameworksSin, Maria 19 January 2019 (has links)
The present thesis deals with the investigation of liquid-phase and gas-phase adsorption of metal-organic frameworks (MOFs) using NMR spectroscopy. NMR-based methods are developed and then applied to characterize the surface polarity of studied materials and the influence of structural flexibility on the adsorption selectivity.
In the first part of the thesis a new methodology for surface polarity screening of MOFs is proposed based on quantitative 1H NMR spectroscopic measurements of liquid-phase adsorption. The influence of the surface polarity on the adsorption process was studied on several materials, e.g. activated carbons, PAF-1, MIL-101(Cr), HKUST-1, and UiO-67-series. The surface polarity was characterized through the difference in the 1,4-dioxane adsorption uptake from two solvents of opposite polarity, namely n-heptane and N,N-dimethylformamide. An NMR-derived surface polarity index was defined where the polarity of the MOF corresponds to its affinity to polar substances. It was demonstrated that the structural modifications of MOF materials, which should affect the polarity of these MOFs, are indeed reflected by the proposed polarity index.
The second part of the thesis focuses on gas mixture adsorption experiments. Metal-organic frameworks are promising candidates for selective separation processes such as CO2 from methane. Framework flexibility is observed only for some special MOFs. The main question is: Does framework flexibility influence the adsorption selectivity? High-pressure in situ 13C NMR spectroscopy was used to monitor the adsorption of 13CO2/13CH4 gas mixtures. This method allows to distinguish between the two gases as well as between adsorbed molecules and the interparticle gas phase. Gas mixture adsorption was performed under isothermal conditions. The selectivity factor for CO2 adsorption from CO2/CH4 mixtures was measured as a function of total gas pressure. The flexible material SNU-9 as well as the flexible and the non-flexible forms of DUT-8(Ni) were compared. Maximum selectivity factors for CO2 were observed for the flexible form of DUT-8(Ni) in its open-pore state. In contrast, the rigid form of DUT-8(Ni) and SNU-9 especially in its intermediate state exhibit lower adsorption selectivity factors. This observation indicates significant influence of the framework flexibility on the adsorption selectivity.
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