DNA robots spin gold in molecular factory

If you thought nanobots might give us cause for concern when the singularity occurs, how about nanobots made from DNA? U.S. scientists have developed microscopic robots composed of DNA that can follow instructions and work together like an assembly line to make products such as particles of gold.

Is this what our future robot workers will be made of?

(Credit: Wikimedia Commons)

Reporting in the journal Nature, New York University chemistry professor Nadrian Seeman and colleagues describe a tiny DNA factory consisting of a DNA track for assembly, three molecular forklifts that can deliver parts, and a DNA "walker" that moves around like a car on an assembly line.

The team had produced the first such DNA walker in 2004, knitting together strands of DNA to form a mobile molecule. With the walker working in the nano-factory, the plant can be programmed to produce up to eight different combinations of gold nanoparticle chemical species, according to the researchers.

"We have the three robot stations lined up in a row, and the walker walks by them. Depending on how we program the system, the walker will or will not accept cargos from the three stations," Seemen told Nature Podcast. "This is very analogous, in my mind, to the way the chassis of a car rolls by the various robots in an automobile assembly line."

The research takes advantage of DNA's unique ability to store information, which the team manipulated to adjust the structure of the molecular robots and how they connect to other molecules. Adding DNA strands to the walker and the forklifts allows them to move.

Another study appearing in Nature featured a programmable DNA walker that could start, stop, and turn. Led by Columbia University biochemist Milan Stojanovic, the scientists got the walker to move down a path 100 nanometers long, an unprecedented feat. The robot could follow a complex curve or a straight line.

Though random walkers had been developed before, the team made their robot move around by manipulating how it interacts with the landscape. In effect, chemical commands to "stop," "start," or "turn" were programmed into the DNA environment, so that once the robot sensed an order, it would carry it out.

The researchers speculate that with further development, the robot could be replicated to do computation tasks or deliver agents into specific cells.

At the least, this would make a good plot device for a film if it hasn't already been done.