Now, a ‘molecular robot’ to follow instructions

The robot follows instructions programmed into a set of fuel molecules determining its destination.

Last Updated: Mar 11, 2011, 00:30 AM IST

Washington: A programmable ‘molecular robot’, a sub-microscopic molecular machine made of synthetic DNA that moves between track locations separated by 6nm, has been developed by researchers.

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 work represents a step toward futuristic nanomachines and nanofactories.

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.

They 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 study appears in ACS`s Nano Letters.