Ong, T.-C., et al., Solvent-Free Dynamic Nuclear Polarization of Amorphous and Crystalline ortho-Terphenyl. The Journal of Physical Chemistry B, 2013. 117(10): p. 3040-3046.
Dynamic nuclear polarization (DNP) of amorphous and crystalline ortho-terphenyl (OTP) in the absence of glass forming agents is presented in order to gauge the feasibility of applying DNP to pharmaceutical solid-state nuclear magnetic resonance experiments and to study the effect of intermolecular structure, or lack thereof, on the DNP enhancement. By way of 1H?13C cross-polarization, we obtained a DNP enhancement (?) of 58 for 95% deuterated OTP in the amorphous state using the biradical bis-TEMPO terephthalate (bTtereph) and ? of 36 in the crystalline state. Measurements of the 1H T1 and electron paramagnetic resonance experiments showed the crystallization process led to phase separation of the polarization agent, creating an inhomogeneous distribution of radicals within the sample. Consequently, the effective radical concentration was decreased in the bulk OTP phase, and long-range 1H?1H spin diffusion was the main polarization propagation mechanism. Preliminary DNP experiments with the glass-forming anti-inflammation drug, indomethacin, showed promising results, and further studies are underway to prepare DNP samples using pharmaceutical techniques.
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25K
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25K
January 2013
Publication year: 2013
Source:Journal of Magnetic Resonance, Volume 226</br>
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We describe an apparatus for solid state nuclear magnetic resonance (NMR) with dynamic nuclear polarization (DNP) and magic-angle spinning (MAS) at 20–25K and 9.4Tesla. The MAS NMR probe uses helium to cool the sample space and nitrogen gas for MAS drive and bearings, as described earlier , but also includes a corrugated waveguide for transmission of microwaves from...
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12-15-2012 09:51 AM
Dynamic nuclear polarization at high magnetic fields in liquids
Dynamic nuclear polarization at high magnetic fields in liquids
July 2012
Publication year: 2012
Source:Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 64</br>
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Graphical abstract
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12-15-2012 09:51 AM
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25 K
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25 K
Available online 20 November 2012
Publication year: 2012
Source:Journal of Magnetic Resonance</br>
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We describe an apparatus for solid state nuclear magnetic resonance (NMR) with dynamic nuclear polarization (DNP) and magic-angle spinning (MAS) at 20-25 K and 9.4 Tesla. The MAS NMR probe uses helium to cool the sample space and nitrogen gas for MAS drive and bearings, as described earlier (Thurber et al., J. Magn. Reson. 2008) , but also includes a...
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12-01-2012 06:10 PM
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25 K
Solid state nuclear magnetic resonance with magic-angle spinning and dynamic nuclear polarization below 25 K
Publication year: 2012
Source:Journal of Magnetic Resonance</br>
Kent R. Thurber, Alexey Potapov, Wai-Ming Yau, Robert Tycko</br>
We describe an apparatus for solid state nuclear magnetic resonance (NMR) with dynamic nuclear polarization (DNP) and magic-angle spinning (MAS) at 20-25 K and 9.4 Tesla. The MAS NMR probe uses helium to cool the sample space and nitrogen gas for MAS drive and bearings, as described earlier (Thurber et al., J. Magn. Reson. 2008) ,...
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11-21-2012 04:33 AM
A 250 GHz Gyrotron with a 3 GHz Tuning Bandwidth for Dynamic Nuclear Polarization
A 250 GHz Gyrotron with a 3 GHz Tuning Bandwidth for Dynamic Nuclear Polarization
Publication year: 2012
Source:Journal of Magnetic Resonance</br>
Alexander B. Barnes, Emilio A. Nanni, Judith Herzfeld, Robert G. Griffin, Richard J. Temkin</br>
We describe the design and implementation of a novel tunable 250 GHz gyrotron oscillator with >10 W output power over most of a 3 GHz band and >35 W peak power. The tuning bandwidth and power are sufficient to generate a >1 MHz nutation frequency across the entire nitroxide EPR lineshape for cross effect DNP, as well as to...
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03-30-2012 10:45 AM
Solution NMR of Polypeptides Hyperpolarized by Dynamic Nuclear Polarization.
Solution NMR of Polypeptides Hyperpolarized by Dynamic Nuclear Polarization.
Solution NMR of Polypeptides Hyperpolarized by Dynamic Nuclear Polarization.
Anal Chem. 2011 Jun 7;
Authors: Ragavan M, Chen HY, Sekar G, Hilty C
Hyperpolarization of nuclear spins through techniques such as Dynamic Nuclear Polarization (DNP) can greatly increase the signal to noise ratio in NMR measurements, thus eliminating the need for signal averaging. This enables the study of many dynamic processes which would otherwise not be amenable to study by NMR spectroscopy....
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06-10-2011 11:52 AM
Surface Enhanced NMR Spectroscopy by Dynamic Nuclear Polarization
Surface Enhanced NMR Spectroscopy by Dynamic Nuclear Polarization
Anne Lesage, Moreno Lelli, David Gajan, Marc A. Caporini, Veronika Vitzthum, Pascal Mie?ville, Johan Alauzun, Arthur Roussey, Chloe? Thieuleux, Ahmad Medhi, Geoffrey Bodenhausen, Christophe Cope?ret and Lyndon Emsley
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja104771z/aop/images/medium/ja-2010-04771z_0004.gif
Journal of the American Chemical Society
DOI: 10.1021/ja104771z
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA...
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09-11-2010 01:25 AM
Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR.
Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR.
Related Articles Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR.
Phys Chem Chem Phys. 2010 Jun 14;12(22):5799-803
Authors: Matsuki Y, Takahashi H, Ueda K, Idehara T, Ogawa I, Toda M, Akutsu H, Fujiwara T
Instrumentation for high-field dynamic nuclear polarization (DNP) at 14.1 T was developed to enhance the nuclear polarization for NMR of solids. The gyrotron generated 394.5 GHz submillimeter (sub-mm) wave with a power of 40 W in the second harmonic...