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Updated: Jun 25, 2026
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
An isotropic chemical shift-chemical shift anisotropic correlation experiment using discrete magic angle turning
Jian Zhi Hu1, Jesse A Sears, Ja Hun Kwak
1Institute for Interfacial Catalysis, Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MS K8-98, Richland, WA 99352, USA. Jianzhi.Hu@pnl.gov
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|February 28, 2009
Summary
A new method called discrete magic angle turning (DMAT) enhances 2D correlation spectroscopy by combining clockwise and anticlockwise sample rotations. This technique provides high-resolution spectra for biological fluids and enables in situ NMR studies.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Analytical Chemistry
- Biophysical Chemistry
Background:
- Magic Angle Turning (MAT) and Magic Angle Hopping (MAH) are established techniques in NMR spectroscopy for simplifying complex spectra.
- Existing methods face limitations in achieving high resolution for certain spin interactions in biological samples.
- There is a need for advanced NMR techniques that allow for real-time monitoring of samples under varying physical conditions.
Purpose of the Study:
- To introduce a novel 2D correlation spectroscopy technique, discrete magic angle turning (DMAT).
- To combine the benefits of MAT and MAH technologies into a single, more versatile method.
- To enable high-resolution spectral analysis of rank-2 spin interactions in biological fluids and facilitate in situ NMR investigations.
Main Methods:
- Developed a DMAT technique involving synchronized clockwise and anticlockwise sample rotations (240-360 degrees).
- Employed a specialized radio frequency (RF) pulse sequence synchronized with the sample's back-and-forth rotation.
- Analyzed spin interactions (chemical shift anisotropy, magnetic susceptibility, dipolar interactions) in biological fluid samples.
Main Results:
- Generated isotropic-anisotropic shift 2D correlation spectra.
- Achieved high-resolution spectra by projecting along the isotropic dimension.
- Demonstrated the potential for in situ control of physical parameters (pressure, flow, temperature) due to limited sample rotation.
Conclusions:
- DMAT is an effective method for obtaining high-resolution NMR spectra of biological fluids.
- The technique simplifies the analysis of various rank-2 spin interactions.
- DMAT facilitates true in situ NMR investigations, allowing for real-time monitoring of samples under dynamic conditions.
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