Publications by authors named "Fatemeh Khashami"

Glassing matrix deuteration could be a beneficial sample preparation method for C dynamic nuclear polarization (DNP) when large electron paramagnetic resonance (EPR) width free radicals are used. However, it could yield the opposite DNP effect when samples are doped with small EPR width free radicals. Herein, we have investigated the influence of solvent deuteration on the C nuclear and electron relaxation that go along with the effects on C DNP intensities at 3.

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Dynamic nuclear polarization (DNP) via the dissolution method is one of the most successful methods for alleviating the inherently low Boltzmann-dictated sensitivity in nuclear magnetic resonance (NMR) spectroscopy. This emerging technology has already begun to positively impact chemical and metabolic research by providing the much-needed enhancement of the liquid-state NMR signals of insensitive nuclei such as C by several thousand-fold. In this Perspective, we present our viewpoints regarding the key elements needed to maximize the NMR signal enhancements in dissolution DNP, from the very core of the DNP process at cryogenic temperatures, DNP instrumental conditions, and chemical tuning in sample preparation to current developments in minimizing hyperpolarization losses during the dissolution transfer process.

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Using a home-built cryogen-free dynamic nuclear polarization (DNP) system with a variable magnetic field capability, C spin-lattice T relaxation times of hyperpolarized [1-C] carboxylates (sodium acetate, glycine, sodium pyruvate, and pyruvic acid) doped with trityl OX063 free radical were systematically measured for the first time at different field strengths up to 9 T at T = 1.8 K. Our data reveal that the C T values of these frozen hyperpolarized C samples vary drastically with the applied magnetic field B according to an apparent empirical power-law dependence (C T ∝ B, 2.

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