Heart cells could propel sperm-like robots (seriously) through the body to deliver medicine

In the 1966 film “Fantastic Voyage,” a CIA agent and his crew shrink down inside a submarine to venture inside a scientist’s body to remove a life-threatening blood clot. Younger readers might remember a similarly intense episode of “Rugrats.”

It’s a concept that actually interests scientists; focus your attack on a disease or infection, and you reduce how much of a patient’s body has to undergo exposure to harsh treatments. Last December, a team at the Leibniz Institute for Solid State and Materials Research in Dresden demonstrated an interesting solution (in German): trap a sperm in a tiny metal tube and coax it in a specific direction with a magnet, and you can convince it to swim in any direction inside the body.

Today, University of Illinois researchers published a paper (subscription required) in Nature Communications describing a sperm-like robot that accomplishes a similar goal. The bot is capable of swimming on its own in liquids similar to those found inside the body.

The robot is made out of a piece of flexible polymer, which is fashioned into a head and tail. Living heart cells are added at the top of the tail. They automatically begin to beat together, which sends a wave down the tail that causes it to wriggle and move the bot forward.

Swimming biobot

“It’s the minimal amount of engineering — just a head and a wire,” team lead Taher Saif said in a release. “Then the cells come in, interact with the structure, and make it functional.”

The researchers are interested in adding light or chemical sensing abilities to the bots. If a patient has, say, a tumor, a chemical or glowing dye could be added to draw medicine carrying robots toward it. The research team was able to build a two-tailed robot, which would help it navigate inside the body.

“The long-term vision is simple,” Saif said in the release. “Could we make elementary structures and seed them with stem cells that would differentiate into smart structures to deliver drugs, perform minimally invasive surgery or target cancer?”

Check out a video of the robots swimming here.