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Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
Two-dimensional (13)C-(13)C correlation spectroscopy with magic angle spinning and dynamic nuclear polarization
Melanie Rosay1, Volker Weis, Kenneth E Kreischer
1Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Journal of the American Chemical Society
|March 28, 2002
Summary
Dynamic nuclear polarization (DNP) significantly enhances solid-state Nuclear Magnetic Resonance (NMR) sensitivity by transferring electron polarization to nuclei. This study demonstrates stable, high-field MAS/DNP experiments, achieving signal boosts up to 23-fold.
Area of Science:
- Solid-state Nuclear Magnetic Resonance (NMR) spectroscopy
- Dynamic Nuclear Polarization (DNP)
Background:
- Dynamic Nuclear Polarization (DNP) is a technique to enhance Nuclear Magnetic Resonance (NMR) sensitivity.
- DNP transfers high Boltzmann polarization from unpaired electrons to nuclei, amplifying NMR signals.
Purpose of the Study:
- To demonstrate enhanced sensitivity in solid-state NMR experiments using DNP.
- To showcase the stability and feasibility of Magic Angle Spinning (MAS)/DNP at high magnetic fields.
- To present the first 2D MAS/DNP experiments at high field.
Main Methods:
- Utilized a custom-designed high-power gyrotron for DNP at 5 T and low temperatures (85-90 K).
- Employed Magic Angle Spinning (MAS) to improve spectral resolution.
- Conducted (1)H-driven (13)C spin-diffusion experiments on proline for stability assessment.
Main Results:
- Achieved signal enhancements of up to 23-fold in MAS experiments.
- Demonstrated extended stability of MAS/DNP experiments at low temperatures.
- Acquired the first two-dimensional (13)C-(13)C chemical shift correlation spectra using MAS/DNP at high field (>1.4 T).
Conclusions:
- High-power gyrotron-based DNP significantly enhances solid-state NMR sensitivity at high fields.
- MAS/DNP experiments are stable and feasible at low temperatures and high magnetic fields.
- This work paves the way for advanced 2D solid-state NMR studies with DNP enhancement.
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