Fawzi, N.L. et al. Nature advance online publication (30 October 2011).

Biology is full of interactions between free molecules in solution and a large supramolecular structure or surface. Fawzi et al. present a way to study such interactions at the atomic level with solution nuclear magnetic resonance (NMR) spectroscopy, with a method called dark-state exchange saturation transfer (DEST). They applied DEST to study the exchange reaction between amyloid-β monomers and very large protofibrils (too large to be observed with NMR spectroscopy)—a process implicated in Alzheimer's disease.