The researchers say they are just scratching the surface of what is possible, with their work potentially leading to millimeter-scale medical or environmental sensors that that can seek out and neutralize harmful toxins.

 

The bio-bots, which are made primarily out of a flexible hydrogel, move using a long leg that acts like a flagellum. The leg is coated with heart cells from the common rat so that when the cells beat, they cause the leg to swing, thrusting the robot forward. For now, the bio-bot is only able to move forward at a fairly constant rate, but the team hopes they'll be able to control the robot's movements by adding neurons, or cells that react to light. Cells that respond to specific chemicals could also give the bio-bots sensor-like qualities.

 

 “Our goal is to see if we can get this thing to move toward chemical gradients, so we could eventually design something that can look for a specific toxin and then try to neutralize it,” said Rashid Bashir, a professor of engineering and director of the Micro and Nanotechnology Laboratory.