Clear-cut observation of PNA invasion using nanomechanical DNA origami devicesThis article is part of the 'Nucleic acids: new life, new materials' web themed issue.Electronic supplementary information (ESI) available: detailed experimental procedures, mass analysis of bis-PNA, counted numbers of the motifs in AFM images, and sequences of the staple strands. See DOI: 10.1039/c2cc36358e

Invasive binding event of PNA into DNA duplex was clearly observed both by atomic force microscope (AFM) imaging and electrophoretic mobility shift assay (EMSA) with the aid of nanomechanical DNA origami devices as 'single-molecule' visual probes, showing their potential as universal platform for the analysis of PNA invasion. Invasive binding event of PNA into DNA duplex was clearly observed both by atomic force microscope (AFM) imaging and electrophoretic mobility shift assay (EMSA) with the aid of nanomechanical DNA origami devices as 'single-molecule' visual probes.