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Updated: Jun 6, 2025
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Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
Published on: November 12, 2016
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High-field SABRE pulse sequence design for chemically non-equivalent spin systems
Danil A Markelov1,2, Vitaly P Kozinenko1, Alexey S Kiryutin1
1International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia.
The Journal of Chemical Physics
|December 3, 2024
Summary
Signal amplification by reversible exchange (SABRE) enhances NMR sensitivity using parahydrogen. This study introduces a new pulse sequence for efficient 15N hyperpolarization in chemically non-equivalent SABRE complexes, broadening substrate applicability.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Hyperpolarization Techniques
- Quantum Chemistry
Background:
- Signal Amplification by Reversible Exchange (SABRE) utilizes parahydrogen to enhance NMR signals.
- High-field SABRE hyperpolarization is sensitive to the spin system's chemical equivalence.
- Efficient hyperpolarization in chemically non-equivalent systems remains a significant challenge.
Purpose of the Study:
- To develop an efficient method for 15N hyperpolarization in chemically non-equivalent SABRE complexes.
- To overcome limitations in current high-field SABRE techniques.
- To expand the range of substrates amenable to SABRE hyperpolarization.
Main Methods:
- Development of a multinuclear 1H-15N pulse sequence.
- Simultaneous 1H and 15N radiofrequency excitation using weak continuous wave magnetic fields.
- Application to SABRE complexes involving parahydrogen and substrates.
Main Results:
- Achieved efficient 15N hyperpolarization in chemically non-equivalent SABRE complexes.
- Demonstrated 15N polarization in antimicrobial drugs at natural isotopic abundance.
- Enabled precise assignment of SABRE complexes responsible for polarization transfer.
Conclusions:
- The novel pulse sequence effectively enables 15N hyperpolarization in challenging non-equivalent SABRE systems.
- This advancement broadens the scope of SABRE applications in chemical and biological research.
- The method facilitates the study of specific molecular interactions and drug mechanisms.
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