Low-power polarization transfer between deuterons and spin-1/2 nuclei using adiabatic RESPIRATIONCP in solid-state NMR

Establishing high-resolution structures of biological macromolecules in heterogeneous environments by MAS solid-state NMR is an important challenge where development of advanced experimental procedures is in high demand. Promising new methods take advantage of samples with extensive 2H, 13C, and 15N isotope labelling, effectively diluting 1H spins. In many cases, a sufficient amount of 1H at exchangeable sites cannot be re-established during the purification procedure, hence it is necessary to exploit also the potential of 2H as a starting point in pulse sequences, capitalizing on its short T1 as compared to 13C, and to detect carbon or proton spins as appropriate. Here we present a new method that enables the required high-efficiency 2H to 13C or 15N polarization transfer to be accomplished under the limited 2H rf power conditions using current 1H, 2H, 13C and 15N quadruple-resonance MAS NMR instrumentation.