By using swarms of untethered grippers, each as small as a
speck of dust, Johns Hopkins engineers and physicians say they have devised a
new way to perform biopsies that could provide a more effective way to access
narrow conduits in the body as well as find early signs of cancer or other
diseases.
In two recent peer-reviewed journal articles, the team
reported successful animal testing of the tiny tools, which require no
batteries, wires or tethers as they seize internal tissue samples. The devices
are called “mu-grippers,” incorporating the Greek letter that represents the
term for “micro.” Instead of relying on electric or pneumatic power, these
star-shaped tools are autonomously activated by the body’s heat, which causes
their tiny “fingers” to close on clusters of cells. Because the tools also
contain a magnetic material, they can be retrieved through an existing body
opening via a magnetic catheter.