Microjaws chomp cells to change them.

Roving microscopic machines may someday battle illness inside bodies. Taking a step in that futuristic direction, researchers in New Mexico have invented a minuscule device that seizes individual red blood cells in its jaws.

Demonstrating that micromechanical gadgets (SN: 7/22/00, p. 56) can manipulate individual cells is an important milestone for biomedical research, says Jay Jakubczak of Sandia National Laboratories in Albuquerque, a manager of the group that made the device. The gadget, announced by the team in August, should offer researchers a new tool for studying cells, he adds.

So far, the jaws only grab and deform cells. After further development, however, they should also be able to puncture cells and insert proteins or drugs, the researchers say. It may be possible to integrate such a design into machines that sort cells for scientific and medical purposes. Making mobile microjaws to fight disease in the body would require surmounting more design hurdles, Jacubczak notes.

The team built the device inside a 20-micrometer-wide channel on a chip. Getting a thick but smooth layer of biologically inert silicon nitride to adhere to the silicon was a major challenge. "The big driver here was figuring out how to get silicon to handle fluids that cells live in," Jakubczak says.