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Preparation of Fungal and Plant Materials for Structural Elucidation Using Dynamic Nuclear Polarization Solid-State NMR
Published on: February 12, 2019
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Isotropic Hyperfine Interactions Drive Cross-Effect Dynamic Nuclear Polarization
Nitzan Livni1, Subhradip Paul2,3, Ilia B Moroz1
1Chemical and Biological Physics, Weizmann institute of science, Rehovot, 761000, Israel.
The Journal of Physical Chemistry Letters
|November 7, 2025
Summary
This study introduces a new method for dynamic nuclear polarization (DNP) using isotropic interactions to enhance solid-state NMR sensitivity. This approach improves efficiency and broadens the applicability of DNP in materials science.
Area of Science:
- Solid-state Nuclear Magnetic Resonance (ssNMR) Spectroscopy
- Dynamic Nuclear Polarization (DNP)
Background:
- Solid-state NMR spectroscopy suffers from low sensitivity, limiting its applications.
- Dynamic Nuclear Polarization (DNP) enhances ssNMR sensitivity by transferring electron spin polarization to nuclear spins.
- The most efficient DNP mechanism in solids, cross-effect (CE), typically requires specific anisotropic electron spin interactions.
Purpose of the Study:
- To present an alternative approach for achieving the cross-effect (CE) condition in DNP using isotropic interactions.
- To make CE-DNP independent of sample orientation and MAS frequency.
- To enable the use of fast-relaxing polarizing agents in DNP experiments.
Main Methods:
- Utilizing isotropic hyperfine interactions between electron spins and nuclear spins.
- Employing Mn(II) dopants as polarizing agents.
- Conducting experimental and simulation-based feasibility studies.
Main Results:
- Demonstrated that isotropic interactions can fulfill the CE condition for DNP.
- Achieved DNP enhancements independent of sample orientation and MAS frequency.
- Showcased the use of Mn(II) dopants and their isotropic hyperfine interactions with 55Mn.
Conclusions:
- The proposed method offers a novel and versatile route for cross-effect DNP.
- This approach enhances the practicality and efficiency of DNP in solid-state NMR.
- The findings pave the way for broader applications of DNP in various scientific fields.
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