Two-dimensional 13C-13C correlation spectroscopy with magic angle spinning and dynamic nuclear polarization

The sensitivity of solid-state NMR experiments can be enhanced with dynamic nuclear polarization (DNP), a technique that transfers the high Boltzmann polarization of unpaired electrons to nuclei. Signal enhancements of up to 23 have been obtained for magic angle spinning (MAS) experiments at 5 T and 85-90 K using a custom-designed high-power gyrotron. The extended stability of MAS/DNP experiments at low temperature is demonstrated with 1H-driven 13C spin-difusion experiments on the amino acid proline. These 13C-13C chemical shift correlation spectra are the first two-dimensional MAS/DNP experiments performed at high field (>1.4 T). Copyright © 2002 American Chemical Society.