Tiny robots swim through blood, deliver drugs — and then dissolve
A tiny bead filled with a drug is guided by magnets to parts of the body, a trial in animals has shown.
By Elizabeth Gibney, Nature, 13 November 2025
A remote-controlled robot the size of a grain of sand can swim through blood vessels to deliver drugs before dissolving into the body. The technology could allow doctors to administer small amounts of drugs to specific sites, avoiding the toxic side effects of body-wide therapies.
The microrobots — guided by magnetic fields — work in blood vessels in pigs and sheep, researchers showed in a paper published in Science on 13 November….
The team says the microrobots would allow smaller amounts of drugs to be given directly to the affected areas, thereby reducing potential side effects. The technique could be used to target stroke-causing blockages or brain tumours…
The system developed by the ETH team involves filling a tiny bead of gelatine with a drug, as well as nanoparticles of magnetic iron oxide, which allows its movement to be controlled by magnetic fields surrounding the patient…. [end quote]
This is very cool! The controlling magnetic fields can move the bot quite fast (up to 40 centimeters per second). By fluctuating the magnetic field rapidly the iron oxide can be heated up to dissolve the gelatin and deliver the drug.
The ability to work inside the body using catheters is delivering great benefits to patients already. “Interventional cardiologists” thread stents and valves into hearts. “Interventional pulmonologists” take samples of nodules and deliver valves into lungs.
This new technique delivers the drug with pinpoint accuracy and doesn’t even need a catheter since it’s guided by a magnetic field from outside. Wow!
Wendy
