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Adiabatic Rotor-Echo-Short-Pulse-Irradiation mediated cross-polarization
Anders B Nielsen1, Sheetal Jain2, Matthias Ernst1
1Physical Chemistry, ETH Zürich, Wolfgang-Pauli-Strasse 10, 8093 Zürich, Switzerland.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|November 14, 2013
Summary
A novel adiabatic-(RESPIRATION)CP method enhances heteronuclear polarization transfer in solid-state Nuclear Magnetic Resonance (NMR) under magic-angle-spinning (MAS). This technique improves efficiency and robustness, especially with radiofrequency field inhomogeneities.
Area of Science:
- Solid-state Nuclear Magnetic Resonance (NMR) spectroscopy.
- Advanced pulse sequence development for Nuclear Magnetic Resonance (NMR).
- Biomolecular structure determination and dynamics.
Background:
- Heteronuclear polarization transfer is crucial for solid-state NMR.
- Existing dipolar recoupling methods face challenges with radiofrequency (rf) field inhomogeneities and resonance offsets.
- The (RESPIRATION)CP technique offers a basis for improved polarization transfer.
Purpose of the Study:
- To introduce a new, efficient, and robust dipolar recoupling method for solid-state NMR.
- To enhance heteronuclear polarization transfer under magic-angle-spinning (MAS) conditions.
- To overcome limitations of existing methods regarding rf-field inhomogeneities and resonance offsets.
Main Methods:
- Development of the adiabatic-(RESPIRATION)CP pulse sequence.
- Combining (RESPIRATION)CP with amplitude modulation of rotor-synchronized pulses.
- Numerical simulations and experimental validation using uniformly (13)C,(15)N-labeled alanine and ubiquitin samples.
Main Results:
- Achieved high heteronuclear polarization transfer efficiencies.
- Demonstrated robustness against rf-field inhomogeneities and resonance offsets.
- Adiabatic-(RESPIRATION)CP showed advantages over standard sequences, particularly in high rf inhomogeneity scenarios.
Conclusions:
- The adiabatic-(RESPIRATION)CP method provides an efficient and robust approach for heteronuclear polarization transfer in solid-state NMR.
- This technique is particularly beneficial for samples experiencing significant rf-field inhomogeneities.
- The method advances capabilities for structural and dynamic studies of biomolecules using solid-state NMR.
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