The Once and Future Nanomachine; September 2001; Scientific American Magazine; by George M. Whitesides; 6 Page(s)

AMONG THE PROMISED FRUITS of nanotechnology, small machines have always stood out. Their attraction is straightforward. Large machines-airplanes, submarines, robotic welders, toaster ovens-are unquestionably useful. If one could take the same ideas used to design these devices and apply them to machines that were a tiny fraction of their size, who knows what they might be able to do?

Imagining two types of small machines-one analogous to an existing machine, the second entirely new-has captured broad attention. The first is a nanoscale submarine, with dimensions of only a few billionths of a meter-the length of a few tens or hundreds of atoms. This machine might, so the argument goes, be useful in medicine by navigating through the blood, seeking out diseased cells and destroying them.