An Alderman-Grant resonator for S-Band Dynamic Nuclear Polarization

作者：Neudert Oliver; Raich Hans Peter; Mattea Carlos; Stapf Siegfried; Muennemann Kerstin

来源：Journal of Magnetic Resonance, 2014, 242: 79-85.

DOI：10.1016/j.jmr.2014.02.001

• Hyperpolarization
• Dynamic Nuclear Polarization
• Overhauser DNP
• Alderman-Grant resonator
• Field cycling NMR
• Time domain NMR
• Low field NMR
• Relaxometry

An Alderman-Grant resonator with resonance at 2 GHz (S-Band) was simulated, developed and constructed for Dynamic Nuclear Polarization (DNP) experiments at 73 mT. The resonator fits into magnet bores with a minimum diameter of 20 mm and is compatible with standard 3 mm NMR tubes. The compact resonator design achieves good separation of electric and magnetic fields and therefore can be used with comparatively large sample volumes with only small sample heating effects comparable to those obtained with optimized X- and W-Band DNP setups. The saturation efficiency and sample heating effects were investigated for Overhauser DNP experiments of aqueous solutions of TEMPOL radical, showing relative saturation better than 0.9 and sample heating not exceeding a few Kelvin even at high microwave power and long irradiation time. An application is demonstrated, combining the DNP setup with a commercial fast field cycling NMR relaxometer. Using this resonator design at low microwave frequencies can provide DNP polarization for a class of low-field and time-domain NMR experiments and therefore may enable new applications that benefit from increased sensitivity.

• 出版日期2014-5