Colorimetric Sensors: Distance‐Mediated Plasmonic Dimers for Reusable Colorimetric Switches: A Measurable Peak Shift of More than 60 nm (Small 2/2013)

The picture shows an approach to real-time monitoring of single molecular binding events by the construction of a reconfigurable colorimetric DNA switch, described on page 234. A significant spectral shift of over 60 nm is achievable from on–off switching. The switching is based on changing the interparticle distance between gold nanoparticles in dimers, actuated by targeted DNA binding. The extraordinary spectral shift allows the unaided eye to observe single-target biomolecular binding events in real time under a darkfield microscope.