An autonomous and controllable light-driven DNA walking device.

The development of nanotechnology has been largely inspired by the biological world. The complex, but well-organized, living system hosts an array of molecular-sized machines responsible for information processing, structure building and, sometimes, movement. We present here a novel light-powered DNA mechanical device, which is reminiscent of cellular protein motors in nature, especially those of green plants. This walking device, which is based on pyrene- assisted photolysis of disulfide bonds, is capable of autonomous locomotion, with light control of initiation, termination and velocity. Based on DNA sequence design and such physical conditions as temperature and ionic strength, this photon-fueled DNA walker exhibits the type of operational freedom and mechanical speed that may rival protein motors in the future.