Es wurden verschiedene NMR-spektrokopische Messungen an flexiblen und chiralen MOFs durchgeführt. Zur Untersuchung der Porensysteme kamen 129Xe-NMR und 13C-NMR an adsorbiertem CO2 zum Einsatz, während die MOF-Gitter und ihre Wechselwirkungen mit adsorbierten Gastmolekülen mittels 13C- und 1H-MAS-NMR-Spektroskopie studiert wurden. Während DUT-8(Ni) Flexibilität zeigt, weist DUT-8(Cu) ein starres Gitter auf. Die Flexibilität der sogenannten Solid-Solutions hängt in ausgeprägter Weise vom Verhältnis der funktionalisierten bdc-Linker 2,5-bme-bdc und db-bdc ab. Dieses Verhältnis hat zudem einen großen Einfluss auf die Orientierung der adsorbierten CO2-Moleküle. Es wurde erstmals eine Methode vorgestellt, die den Festkörper-NMR-spektroskopischen Nachweis chiraler Seitengruppen in chiralen MOFs erlaubt, wie anhand des chiral modifizierten UMCM-1 (ChirUMCM-1) demonstriert wurde. Die Chiralität kann einen NMR-spektroskopisch messbaren Einfluss auf die intrinsische Dynamik des MOF-Gitters ausüben, wie am chiral modifizierten DUT-32 deutlich wurde, dessen chirale Seitengruppe selektiv 15N- und 13C-isotopenmarkiert wurde.

Porous materials or a porous media can be encountered in our everyday life, both in industrial and household systems and in the nature. Generally speaking all solid and semisolid materials are porous to some degree e.g. different dense rock types, plastics etc. Porous materials are constantly finding more and more applications, both in industry and research. Many commercially important process in the industry utilize porous media e.g. flow of fluids through porous media for separation process and porous catalyst supports. This has strongly contributed to the development of porous media with controlled properties, which can be utilized for understanding the behavior of liquids confined in the material, and the morphology of these synthetic materials.This thesis work brings some insight and understanding of porous materials i.e. Controlled Pore Glass (CPG). Report also contains a brief explanation of Nuclear Magnetic Resonance (NMR) spectroscopy, diffusion NMR and other techniques such as Mercury porosimetry.The first part of the thesis is focused on determining the required amount of liquid i.e. octanol needed to achieve full pore saturation for different CPGs with varying pore sizes. This was achieved by taking into account that the transverse relaxation time T2 is sensitive in the ms-ns of motional correlation times, and that there are physical factors in porous material which affect the T2. Second part, diffusion NMR is used to study self-diffusion of octanol confined in CPG, thus bringing some insight on mass transfer limitations within porous systems. The report present results obtained from experiments with NMR and Diffusion NMR, discusses the issues that can arise when investigating porous materials and suggest solutions.

Ionic liquids are continuously finding more and more applications, both in research and in the industry. Many attempts have been made to find parameters that could be used to describe all ionic liquid systems. Five years ago a Japanese group applied the work of Gutmann on ionic liquids to use ionic association to describe solvation effects. The group calculated ionic association from conductivity and diffusion measurements. This report presents a direct approach through electrophoretic NMR to measure ionic association in ionic liquids.  The report contains a brief introduction to ionic liquids and their properties as well as a short explanation of Nuclear Magnetic Resonance (NMR) spectroscopy, diffusion NMR and a more detailed explanation of electrophoretic NMR (eNMR). Experimental setups, taken from previous work by the NMR group at Physical Chemistry KTH, have been modified to allow for measurements in ionic liquid systems. The report discusses the issues that can arise when measuring eNMR in ionic liquids and suggests solutions. The method developed is principally built upon experiments on 1-butyl-3-methyl-imidazolium trifluoroacetate and is directly applicable to other ionic liquid systems. For more viscous systems than the one investigated here, slight changes will need to be made, as explained in the report.  In order to evaluate the method developed during the project the degree of association for 1-butyl-3-methyl-imidazolium trifluoroacetate has been calculated from experimental results and results in similar values as reported by Tokuda et al.. Furthermore, the temperature variation due to Joule heating during a complete eNMR experiment was also investigated by observing change in chemical shift.

PNIPAM (poly(N-Isopropylacrylamide)) is a well-known thermoresponsive polymer. Dissolved in water, it shows a structural change at 32 oC, above which the polymer folds together, and a phase separation occurs. The temperature where the polymer changes structure is known as the LCST (Lower Critical Solution Temperature), and can be modified by adding certain salts to the solution [1]. The mechanism by which the ionic components of the salts affect the LCST is not yet completely understood. The purpose of this master thesis is to study this mechanism. In order to investigate the mechanism, a combination of diffusion NMR and electrophoretic NMR was used, giving the effective charge per molecule which is directly proportional to the grade of association of ions to the polymer. The salts tested were: NaCl, NaClO4, NaSO4, NaI, NaSCN and CaCl2 from which the ClO4-, SCN-, and I- ions, as well as Cl- ions from CaCl2, were found to bind to PNIPAM.

The purpose of this thesis was to investigate how crown ethers behave and interact with different cations and to optimise the setup of the electrophoretic NMR. To get a good electrophoretic NMR measurement the electrophoretic phase shift needs to be big. To increase the phase shift some parameters needed to be adjusted, parameters such as the concentration of crown ether and cation, the duration of magnetic field gradient pulse δ, the magnetic field gradient strength g, the diffusion time Δ and the applied voltage V. The main focus then put on crown ethers 15-crown-5 and 18-crown-6. The cations used were lithium (Li), sodium (Na), potassium (K), caesium (Cs), calcium (Ca) and barium (Ba). The effective charge was obtained by using pulsed gradient NMR to derive the diffusion coefficient and electrophoretic NMR to get the electrophoretic mobility. These data were used to calculate the equilibrium constant of the formed complex. The outcome of the investigation: the affinity for 18-crown-6 was in the following order barium > potassium > caesium > sodium > calcium > lithium and for 15-crown-5 barium > sodium > calcium >  caesium >  potassium > lithium.

Pulsed field gradient (PFG) 1H NMR was used to characterize the mobility of ionic liquid cations in porous gas diffusion electrode (GDE) frameworks for metal–air electrochemical systems. The carbon GDE frameworks were produced by electrospinning. It was found that the motion of ionic liquids in the highly porous hosts is more complex than what is commonly exhibited by conventional fluids, which makes a multimodal investigation essential for an adequate description of mobility and wetting of GDEs. Observed NMR diffraction-like patterns cannot be linked to the tortuosity limit but may serve as a proxy for structural features in the fibrous material. While the observed data were interpreted using standard theoretical models, alternative explanations and causes for artifacts are discussed.

Le marquage, la détection et l’étude de protéines in cellulo sont essentiels pour la compréhension au niveau moléculaire des mécanismes biologiques. Des techniques sensibles et qui engendrent peu de perturbations sur le système étudié sont indispensables. Hélas les techniques de pointe historiquement utilisées telles que l’optique font déplorer une forte perturbation du système en raison de la taille imposante des fluorophores utilisés. L’IRM quant à elle possède une sensibilité de détection très faible. Ce projet propose une méthode innovante de détection de protéines en combinant ces deux techniques prometteuses et hautement complémentaires pour une étude moléculaire de processus intracellulaires. Les deux avancées techniques permettant l’élaboration d’un tel projet sont l’utilisation d’un fluorophore activable de très petite taille et l’exploitation de la grande sensibilité d’un gaz non toxique, le xénon, dont le spin nucléaire est hyperpolarisé. Combiner ces deux techniques d’imagerie novatrices permet d’obtenir des informations au niveau moléculaire. Ce projet sera une percée dans le suivi de protéines recombinantes et l’étude des mécanismes intracellulaires associés. In fine, le but est de créer le premier traceur capable de détecter sa cible et de s’activer à la fois en fluorescence et en IRM. / Full understanding of intracellular phenomena involves sensitive and non-invasive detection. A less disruptive method than labeling with fluorescent proteins uses binding between a tag of only six natural amino acids that can be genetically incorporated into the protein of interest and a small molecule called FlAsH. This molecule has the ability to fluoresce only when it binds to its tetracysteine target. Another technique based on 129Xe NMR has emerged. Xenon is hyperpolarized to enhance the NMR signal by orders of magnitude and its reversible encapsulation in functionalized host systems gives it a specific spectral signature. Capability of the noble gas to cross cell membranes without losing its polarization enables in cellulo investigations.This doubly smart probe is highly promising for monitoring, studying, detecting recombinant proteins. Structural, chemical and lateral resolutions are combined by the bimodality of this new concept, which can be extended to in cellulo detection.

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Porous materials or a porous media can be encountered in our everyday life, both in industrial and household systems and in the nature. Generally speaking all solid and semisolid materials are porous to some degree e.g. different dense rock types, plastics etc. Porous materials are constantly finding more and more applications, both in industry and research. Many commercially important process in the industry utilize porous media e.g. flow of fluids through porous media for separation process and porous catalyst supports. This has strongly contributed to the development of porous media with controlled properties, which can be utilized for understanding the behavior of liquids confined in the material, and the morphology of these synthetic materials. This thesis work brings some insight and understanding of porous materials i.e. Controlled Pore Glass (CPG). Report also contains a brief explanation of Nuclear Magnetic Resonance (NMR) spectroscopy, diffusion NMR and other techniques such as Mercury porosimetry. The first part of the thesis is focused on determining the required amount of liquid i.e. octanol needed to achieve full pore saturation for different CPGs with varying pore sizes. This was achieved by taking into account that the transverse relaxation time T2 is sensitive in the ms-ns of motional correlation times, and that there are physical factors in porous material which affect the T2. Second part, diffusion NMR is used to study self-diffusion of octanol confined in CPG, thus bringing some insight on mass transfer limitations within porous systems. The report present results obtained from experiments with NMR and Diffusion NMR, discusses the issues that can arise when investigating porous materials and suggest solutions