Mechanisms of dynamic nuclear polarization in insulating solids

J Magn Reson. 2015 Apr:253:23-35. doi: 10.1016/j.jmr.2015.02.005.

Abstract

Dynamic nuclear polarization (DNP) is a technique used to enhance signal intensities in NMR experiments by transferring the high polarization of electrons to their surrounding nuclei. The past decade has witnessed a renaissance in the development of DNP, especially at high magnetic fields, and its application in several areas including biophysics, chemistry, structural biology and materials science. Recent technical and theoretical advances have expanded our understanding of established experiments: for example, the cross effect DNP in samples spinning at the magic angle. Furthermore, new experiments suggest that our understanding of the Overhauser effect and its applicability to insulating solids needs to be re-examined. In this article, we summarize important results of the past few years and provide quantum mechanical explanations underlying these results. We also discuss future directions of DNP and current limitations, including the problem of resolution in protein spectra recorded at 80-100 K.

Keywords: Cross effect; Dynamic nuclear polarization (DNP); Overhauser effect; Protein NMR; Pulsed DNP.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Algorithms*
  • Electric Conductivity
  • Models, Chemical*
  • Nuclear Magnetic Resonance, Biomolecular / methods*
  • Proteins / analysis*
  • Proteins / chemistry*

Substances

  • Proteins