Enzyme-based machinery could have medical applications
Researchers have created millimeter-sized metal tools that contort on command, clamping shut or popping open in response to specific chemical cues. The smart devices, described online September 17 in the Journal of the American Chemical Society, may one day be used to biopsy a liver, prop open an artery or deliver drugs to a target site.
Even tiny tools need some power source — a battery pack or electrical wires — but that adds unwanted bulk, says study leader David Gracias of Johns Hopkins University in Baltimore. Yet nature is filled with minimachines: muscles contract, leaves turn to the sun, a Venus fly trap snaps shut. “In nature, an