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Masion, A., et al., Dynamic Nuclear Polarization NMR as a new tool to investigate the nature of organic compounds occluded in plant silica particles. Sci Rep, 2017. 7(1): p. 3430.
The determination of the chemical nature of the organic matter associated with phytoliths remains a challenge. This difficulty mainly stems from amounts of organic carbon (C) that are often well below the detection limit of traditional spectroscopic tools. Conventional solid-state 13C Nuclear Magnetic Resonance (NMR) is widely used to examine the nature and structure of organic molecules, but its inherent low sensitivity prohibits the observation of diluted samples. The recent advent of commercial microwave source in the terahertz range triggered a renewed interest in the Dynamic Nuclear Polarization (DNP) technique to improve the signal to noise ratio of solid-state NMR experiments. With this technique, the 13C spectrum of a phytolith sample containing 0.1% w/w C was obtained overnight with sufficient quality to permit a semi-quantitative analysis of the organic matter, showing the presence of peptides and carbohydrates as predominant compounds. Considering the natural abundance of the 13C isotope, this experiment demonstrates that DNP NMR is sufficiently sensitive to observe spin systems present in amounts as low as a few tens of ppm.
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Essentials of Dynamic Nuclear Polarization #DNPNMR
From The DNP-NMR Blog:
Essentials of Dynamic Nuclear Polarization #DNPNMR
Dear Colleague,
It is my pleasure to announce that a limited edition of
`Essentials of Dynamic Nuclear Polarization'
is now available at the UK branch of Amazon: www.amazon.co.uk
Amplifying dynamic nuclear polarization of frozen solutions by incorporating dielectric particles
From The DNP-NMR Blog:
Amplifying dynamic nuclear polarization of frozen solutions by incorporating dielectric particles
Kubicki, D.J., et al., Amplifying dynamic nuclear polarization of frozen solutions by incorporating dielectric particles. J Am Chem Soc, 2014. 136(44): p. 15711-8.
http://www.ncbi.nlm.nih.gov/pubmed/25285480
Fast Characterization of Functionalized Silica Materials by Silicon-29 Surface-Enhanced NMR Spectroscopy Using Dynamic Nuclear Polarization
Fast Characterization of Functionalized Silica Materials by Silicon-29 Surface-Enhanced NMR Spectroscopy Using Dynamic Nuclear Polarization
Moreno Lelli, David Gajan, Anne Lesage, Marc A. Caporini, Veronika Vitzthum, Pascal Mie?ville, Florent He?roguel, Fernando Rasco?n, Arthur Roussey, Chloe? Thieuleux, Malika Boualleg, Laurent Veyre, Geoffrey Bodenhausen, Christophe Cope?ret and Lyndon Emsley
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja110791d/aop/images/medium/ja-2010-10791d_0005.gif
Journal of the American Chemical Society...