Illustration shows a programmable “molecular robot” — a sub-microscopic machine made of synthetic DNA that can move among different branches of a molecular track while carrying cargo. Credit: American Chemical Society |
Scientists
have developed a programmable “molecular robot”—a sub-microscopic
molecular machine made of synthetic DNA that moves between track
locations separated by 6 nm. The robot, a short strand of DNA, follows
instructions programmed into a set of fuel molecules determining its
destination, for example, to turn left or right at a junction in the
track. The report, which represents a step toward futuristic
nanomachines and nanofactories, appears in ACS’s Nano Letters.
Andrew
Turberfield and colleagues point out that other scientists have
developed similar DNA-based robots, which move autonomously. Some of
these use a biped design and move by alternately attaching and detaching
themselves from anchor points along the DNA track, foot over foot, when
fuel is added. Scientists would like to program DNA robots to
autonomously walk in different directions to move in a programmable
pattern, a key to harnessing their potential as cargo-carrying molecular
machines.
The
scientists describe an advance toward this goal—a robot that can be
programmed to choose among different branches of a molecular track,
rather than just move in a straight line. The key to this specialized
movement is a so-called “fuel hairpin,” a molecule that serves as both a
chemical energy source for propelling the robot along the track and as a
routing instruction. The instructions tell the robot which point is
should move to next, allowing the selection between the left or right
branches of a junction in the track, precisely controlling the route of
the robot—which could potentially allow the transport of
pharmaceuticals or other materials.
The authors acknowledged funding from the Engineering and Physical Sciences Research Council (EPSRC).