Longevity science

Just like other parts of the body, the retina needs oxygen in order to survive. If it doesn’t receive enough – should its blood supply be restricted, for instance – permanent blindness can result.

The sooner that doctors know if a patient’s retina is receiving insufficient oxygen, the better the chances that they can take action in time. Soon, they may be able to use tiny injectable robots to get them the information they need.

Using a 3D printer, researchers at the University of Illinois have developed synthetic "bio-bots" about seven millimeters long that are powered by embedded cardiac cells that give them the ability to "walk" on their own.

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.