Less is More in Medicine; September 2001; Scientific American Magazine; by A. Paul Alivisatos; 8 Page(s)

The 1966 film Fantastic Voyage treated moviegoers to a bold vision of nanotechnology applied to medicine: through mysterious means, an intrepid team of doctors and their high-tech submarine were shrunk to minute size so that they could travel through the bloodstream of an injured patient and remove a life-threatening blood clot in his brain. In the past 35 years, great strides have been made in fabricating complex devices at ever smaller scales, leading some people to believe that such forms of medical intervention are possible and that tiny robots will soon be coursing through everyone's veins. Indeed, in some circles the idea is taken so seriously that worries have emerged about the dark side of such technology: Could self-replicating nanometer-scale automatons run amok and destroy the entire biological world?

In my view, shared by most investigators, such thoughts belong squarely in the realm of science fiction. Still, nanotechnology can potentially enhance biomedical research tools-for example, by providing new kinds of labels for experiments done to discover drugs or to reveal which sets of genes are active in cells under various conditions. Nanoscale devices could, moreover, play a part in quick diagnostic screens and in genetic tests, such as those meant to determine a person's susceptibility to different disorders or to reveal which specific genes are mutated in a patient's cancer. Investigators are also studying them as improved contrast agents for noninvasive imaging and as drug-delivery vehicles. The emerging technologies may not be as photogenic as a platelet-size Raquel Welch blasting away at a clot with a laser beam, but they are every bit as dramatic because, in contrast, the benefits they offer to patients and researchers are real.