We present a novel solid-state NMR method for heteronuclear dipolar recoupling without decoupling. The method, which introduces the concept of exponentially modulated rf fields, provides efficient broadband recoupling with large flexibility with respect to hetero- or homonuclear applications, sample spinning frequency, and operation without the need for high-power 1H decoupling. For previous methods, the latter has been a severe source of sample heating, which may cause detoriation of costly samples. The so-called EXPonentially mOdulated Recoupling experimenT (EXPORT) is described analytically and numerically and demonstrated experimentally by 1D 13C spectra and 2D 13C-15N correlation spectra of 13C, 15N-labeled samples of GB1, ubiquitin, and fibrils of the SNNFGAILSS fragment of amylin. Through its flexible operation, robustness, and strong performance, it is anticipated that EXPORT will find immediate application for both hetero- and homonuclear dipolar recoupling in solid-state NMR of 13C,15N-labeled proteins, and compounds of relevance in chemistry.
ASJC Scopus subject areas
- Materials Science(all)
- Physical and Theoretical Chemistry