Today, objects and materials that are manipulated on the nano-scale form essential parts of our everyday life. One important example is electronics, powered by computer chips with miniscule features. Several techniques exist for manufacturing of such materials, most of which rely on top-down approaches. These techniques require careful control of clean-room conditions and are expensive and complicated to implement. In contrast, nature uses bottoms-up approaches to construct atomically precise materials like proteins with a low energy expenditure and extreme speed and precision. Drawing inspiration from the bottoms-up approaches found in nature, DNA nanotechnology use carefully programmed DNA strands to self-assemble complex structures and machines on the nanometre scale. In this project, we aimed at using DNA nanotechnology to produce tiny motors called linear actuators. The plan was to use external control strands to drive the position of the motors and then utilize the motors for nanoscale patterning through the addition of a write-head function.
We found that DNA nanotechnology, specifically through the technique DNA origami could create linear actuators through creating a two-component DNA origami structure consisting of a linear rail and a topologically locked slider structure. The slider was capable of diffusing freely along the rail, and when control strands were added, we could lock it at a programmed position. Importantly, this locking was reversible through the addition of invader strands releasing the slider to diffuse freely again along the rail. We were also able to connect multiple slider devices together to create a 2D gantry where a slider could be positioned in two dimensions over a surface. Finally, we were able to use the slider in the 2D gantry to pattern a canvas at programmed positions.
