micro-robots, USA News: While human shrinking remains confined to science fiction classics like the 1966 film Fantastic Voyage, miniature medical robots are being actively developed by research groups around the globe. This month, a team in Beijing revealed a medical micro-robot designed for delivering drugs to precise locations in the gut, while other international groups are working on devices to destroy tumors, widen arteries, and dissolve blood clots.
Although devices small enough to travel through blood vessels may still be a decade away from regular patient use, NHS doctors are already utilizing a more basic form of medical micro-robot: a swallowable capsule equipped with a tiny camera. These capsules offer an alternative to traditional endoscopies for investigating gut bleeding or pain. While first-generation camera capsules moved passively through the digestive tract, advanced versions can now be maneuvered within the stomach using magnetic steering systems, such as NaviCam, to inspect for ulcers, growths, and cancer.
Precision Drug Delivery and Magnetic Steering
Magnets have emerged as the leading method for steering various medical micro-robots currently in development. Researchers in Beijing have engineered a 6.5mm-diameter “spiny milli-ball robot” meant for drug delivery. Encased in a capsule that dissolves in the stomach, the spiny device uses its spikes to anchor into gut tissue via magnetic pull once it reaches the lower bowels. In animal tests reported in the journal Cyborg and Bionic Systems, the device successfully delivered insulin to the lower intestine of pigs.
Professor Bradley Nelson, a roboticist at ETH Zürich who was not involved in the Beijing study, notes that precision drug delivery can help overcome the issue of toxicity. Approximately one-third of experimental drugs fail clinical trials due to excessive toxicity, but targeted release can significantly reduce the required dose. “We can put the drug right where we want it – that’s the promise of delivering drugs with micro-robots,” Nelson explains.
Targeting Blood Clots and Tumors
Smaller micro-robots designed to rove through the bloodstream have also shown progress. Nelson’s team at ETH Zürich previously demonstrated that a 2mm-wide micro-robot can be magnetically guided through a pig’s bloodstream using a PlayStation controller while monitored via X-ray. In a silicone model of the brain’s circulatory system, the robot successfully delivered a drug to dissolve a blood clot. Researchers suggest similar devices could treat tumors, localize infections, or block blood supply to aneurysms.
Furthermore, Dr. Ali Kafash Hoshiar and his team at the University of Essex have developed drug-containing devices as small as one-tenth of a millimetre, along with simpler magnetic specks. Deployed in swarms, these metallic particles can be steered to surround a cancer and heated via magnetic field changes to destroy tumors, a method already tested in mice. As these technologies advance, researchers believe they will significantly reshape modern medicine.
