On a crisp fall evening in 2006, Dr. Sylvain Martel held his breath as a technician slipped an anesthetized pig into a whirling fMRI machine. His eyes stared intently at a computer screen, which showed a magnetic bead hovering inside the pig’s delicate blood vessels. The tension in the room was palpable.
Suddenly, the bead jumped to life, hopping effortlessly down the vessel like a microsubmarine heading to its next target destination. The team erupted in cheers.
Martel and his team were testing a new way to remotely steer tiny objects inside a living animal by manipulating the magnetic forces of the machine. And for the first time, it worked.
Scientists and writers have long dreamed of tiny robots that navigate the body’s vast circulatory system, like space explorers surveying the galaxies and their inhabitants. The potentials are many: tiny medical microbots could, for example, shuttle radioactive drugs to cancer clusters, perform surgeries inside the body, or clear out blood clots lodged deep inside the heart or brain.
“The dream is the Fantastic Voyage,” but with bots instead of people, says roboticist Dr. Bradley Nelson at ETH Zurich, referencing a classic science fiction movie wherein a team of people are shrunken down and travel through a person’s bloodstream to perform brain surgery on a moribund intelligence agent.
For now, medical microbots are still mostly fictional, though that’s set to change within the decade. Writing in Nature this week, Drs. Mariana Medina-Sánchez and Oliver G. Schmidt at the Leibniz IFW in Dresden, Germany turned away from the big screen to nanoengineering labs, setting out priorities and realistic tests to bring these tiny surgeons to life.
Image Credit: ACS Applied Materials & Interfaces