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Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
High power pulsed dynamic nuclear polarisation at 94 GHz
Robert I Hunter1, Paul A S Cruickshank, David R Bolton
1School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, UK.
Physical Chemistry Chemical Physics : PCCP
|April 30, 2010
Summary
High power pulsed techniques enhance solid state Dynamic Nuclear Polarisation (DNP) in large samples. Short pulses at fast repetition rates yield greater DNP enhancements than continuous wave methods using the same average power.
Area of Science:
- Solid-state Nuclear Magnetic Resonance (NMR) spectroscopy
- Quantum control techniques
Background:
- Dynamic Nuclear Polarisation (DNP) significantly enhances NMR sensitivity.
- Traditional continuous wave (cw) DNP methods require high power and can be inefficient.
- Scaling DNP to high-volume samples presents challenges in maintaining signal enhancement.
Purpose of the Study:
- To investigate the efficacy of high power pulsed techniques for solid-state DNP.
- To compare pulsed DNP performance against conventional cw DNP for large samples.
- To determine optimal pulsing parameters for maximizing DNP enhancement.
Main Methods:
- Utilisation of high power pulsed radiofrequency (RF) techniques at 94 GHz.
- Application of short excitation pulses (comparable to pi/2 pulse length).
- Employing fast repetition rates for pulsed excitation.
Main Results:
- Pulsed DNP excitation achieved higher signal enhancements compared to cw excitation.
- Enhanced DNP observed at low average power levels (few hundred mW).
- Short pulse durations and fast repetition rates are key to improved performance.
Conclusions:
- High power pulsed techniques offer a more efficient approach to solid-state DNP.
- This method is particularly promising for enhancing NMR signals in high-volume samples.
- Further optimisation of pulsed DNP parameters could lead to even greater sensitivity gains.
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