A biological robot powered by the heart cells of rats might someday help people with health problems, according to a report published in the online journal Scientific Reports. Biological engineers at the University of Illinois at Urbana-Champaign have made “bio-bots” by using a 3-D printer, producing thin layers of a gelatinous material like that used in contact lenses, to which are added thousands of heart cells removed from newborn rats. After a few days, the cells begin to twitch in sync, causing the bio-bot to move. Immersed in a nutrient-rich fluid, bio-bots can function for up to two weeks.
For now the creatures are too big, too slow, and too perishable for anything other than research purposes. A quarter of an inch long, they move on two asymmetrical legs at 0.00053 miles per hour and can go in only one direction. Scientists hope to make the tiny machines more useful in the future by using skeletal muscle cells, which live longer and are easier to control than heart cells. Eventually, multicellular bio-bots could be used to sense the chemicals secreted by tumor cells, then neutralize and destroy them. They could also be used to test the effects of new cardiac drugs.
“Many scientists get inspired by science fiction and say, ‘We have the technology to do that,’ ” says Vincent Chan, one author of the new study. “Our project started with a U.S. Army grant to develop a cardiac patch if someone had a heart attack. It turned into a National Science Foundation-funded bio-bot project when we realized our design could actually move.”
When can we expect these little devices to be swimming through our veins? “We’re thinking 10 to 20 years down the road,” says Chan.
