Efficient cross-effect dynamic nuclear polarization without depolarization in high-resolution MAS NMR.

ABSTRACT: Dynamic nuclear polarization (DNP) has the potential to enhance the sensitivity of magic-angle spinning (MAS) NMR by many orders of magnitude and therefore to revolutionize atomic resolution structural analysis. Currently, the most widely used approach to DNP for studies of chemical, material, and biological systems involves the cross-effect (CE) mechanism, which relies on biradicals as polarizing agents. However, at high magnetic fields (≥5 T), the best biradicals used for CE MAS-DNP are still far from optimal, primarily because of the nuclear depolarization effects they induce. In the presence of bisnitroxide biradicals, magic-angle rotation results in a reverse CE that can deplete the initial proton Boltzmann polarization by more than a factor of 2. In this paper we show that these depo

SUBMITTER: Mentink-Vigier F 

PROVIDER: S-EPMC5861987 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature