A switchable surface enables visualization of single DNA hybridization events with atomic force microscopy.

Here we describe a novel surface that enables direct visualization of the hybridization of single DNA molecules with an unprecedented resolution using atomic force microscopy. The surface consists of single-stranded DNA probes that are covalently anchored to a self-assembled monolayer. The surface satisfies the contradictory requirements for high-resolution imaging and hybridization by switching the DNA-surface interaction between a strong state and a weak state. Our approach opens up unique opportunities in elucidating hybridization at the molecular scale.