Swiss scientists at ETH Zurich have developed tiny robots that can swim through your bloodstream and navigate directly to your brain to fight strokes, delivering medication exactly where it’s needed without flooding your entire body with high doses that cause dangerous side effects. The microscopic marvel consists of a spherical gel capsule embedded with medication and equipped with iron oxide nanoparticles that doctors can control from outside the body using magnetic fields, allowing them to steer the robot through the powerful currents of blood pumping through vessels at incredible speeds. Researchers combined three different magnetic navigation strategies that enable them to guide the robot through all regions of head arteries, a remarkable feat considering the force and velocity of blood flow that the navigation system must withstand.
Once the capsule reaches its destination, doctors heat it using a high frequency magnetic field, causing the gel structure to dissolve and release the medication precisely where it’s needed to treat strokes or tumors. The robots are also equipped with tantalum nanoparticle contrast agents that allow doctors to track their journey through the body in real time, though these particles are heavier and more difficult to control. While the technology hasn’t been tested on humans yet, it has already worked successfully in tests on pigs and a sheep, as reported in the journal Science. Lead researcher Fabian Landers marveled at the challenge, saying “it’s incredible how much blood is pumped through our vessels and at what speed,” but the breakthrough proves that targeted drug delivery that once seemed like pure science fiction is now becoming a lifesaving reality.
