Exchange NMR spectroscopy in solids: application in large-scale conformational biopolymer dynamics studies

The exchange NMR experiment compares resonant frequencies of a magnetic nucleus before and after the so-called mixing time, thereby gaining molecular dynamics information on millisecond and second correlation time scales. Although exchange NMR experiments on solutions have a long history, conducting them on solids presents methodological challenges, and it was only in the late 1990s that solid-state exchange spectroscopy matured to the level where such complex entities as biopolymers could be addressed. In this review, major methodological advances in the field are examined and the application of exchange NMR experiments to conformational molecular dynamics of solid-state biopolymers is described.