Miniaturised Wacky Races

Forget Formula 1 – cars the size of molecules came to France to race on a track made of gold. Rob Banino sizes up the competition

People will race anything, given half a chance. Whether it’s motorcars, mammals or lawnmowers, we want to know which is the fastest. A race is also what brought an international group of scientists to Toulouse, France on 14 October – but they visited to race molecules. Molecules that have been engineered to be tiny nanocars.

“A nanocar is a special kind of nano-vehicle,” explains Dr Christian Joachim of the Centre National de la Recherche Scientifique in Toulouse, the nanocar race director. “They’re made of four molecular wheels, a molecular chassis and [in some cases] a molecular motor. All these chemical-mechanical parts are bonded together to form a single, robust molecule.”

Needless to say, a molecule that’s been engineered to drive across an atomic landscape is small – very small. “Wheel diameter is generally less than one nanometre and a chassis is about two to three nanometres long,” says Joachim. One nanometre is one billionth of a metre; the average human hair is about 25,000 nanometres wide.