By powering a DNA nanorobotic arm with electric fields, scientists have achieved precise nano-scale movement that is at least five orders of magnitude faster than previously reported for DNA-driven robotic systems. Their miniscule self-assembling robot may serve as a platform for new inventions in digital memory, cargo transfer and 3-D printing of molecules, says Björn Högberg in a related Perspective. Nanoscale movement in the natural world, such as the self-assembly of DNA, has helped inspire the creation of autonomous nanomachines with far-reaching applications, from biotechnology to computation. However, relying on DNA's molecular cues to instigate movement in these devices can be a slow and inefficient process, which is why Enzo Kopperger and colleagues used a different approach to mobilize their DNA nanorobots: the application of electric fields in a manner similar to how electrophoresis moves and separates large DNA molecules. With this new power source, Kopperger et al.'s robotic system - comprised of a square base and a protruding "arm" all made of DNA double helices - could point and rotate in fixed directions at a much higher speed than when relying on DNA molecular forces alone. The movement resembles the gearshift of a car, with short, single-stranded DNA serving as "latches" to grab and lock the arm into predefined places. The authors also demonstrated their DNA nanorobot's ability to transport nanoparticles back and forth. The fast, computer-controlled and scalable robotic system can be adapted to include more robotic arms, perhaps bringing the research field a step closer to realizing a nanorobotic production factory, the authors say.
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Journal
Science