discovermagazine.com: by Boonsri Dickinson

Snowflake-like robot could be used in biopsies and other procedures.

Researchers have come up with many clever concepts for micro­devices that could perform fine surgery or assemble tiny electronics. In December Johns Hopkins University chemical engineer David Gracias and colleagues announced a big but tiny breakthrough: They had developed a set of microgrippers [pdf] that open and close in reaction to simple chemical changes. The minute machines are able to pick up and put down objects less than 1/500th of an inch across. [ read more ]