Scientists create microscopic robots that navigate blood vessels to treat strokes - Video

Stroke affects 12 million people worldwide each year, often causing death or lasting disability. Current treatments use high doses of clot-dissolving drugs that spread throughout the entire body, leading to serious side effects like internal bleeding. However, researchers at ETH Zurich have developed a groundbreaking microrobot to deliver these drugs directly to the stroke-causing clot, minimizing systemic risks and improving precision.

The microrobot consists of a tiny spherical capsule made of a soluble gel shell containing iron oxide nanoparticles that give it magnetic properties. These nanoparticles allow the capsule to be guided inside the body using an electromagnetic navigation system.

The capsule is injected via a special catheter into the bloodstream or cerebrospinal fluid, then precisely steered to the thrombus with three distinct magnetic navigation methods, enabling it to navigate complex brain vessel networks at speeds up to 4 millimeters per second, even swimming against blood flow exceeding 20 centimeters per second.

The gel capsule also contains the therapeutic agent, such as a clot-dissolving drug, which is released upon application of a high-frequency magnetic field that heats the nanoparticles, dissolving the capsule and freeing the medication exactly where it is needed.

Researchers validated this approach through extensive trials using realistic silicone vessel models and animal tests, achieving drug delivery success in over 95% of cases.

This innovative microrobot system represents a major advance in targeted, minimally invasive stroke therapy and holds promise for treating other localized conditions like infections and tumors. Its development merges robotics, materials science, and medicine, heralding a new era in precision healthcare.

The team is now focused on moving rapidly toward human clinical trials to bring this technology into operating rooms globally, to improve outcomes and offering new hope to stroke patients.

REFERENCE: Fabian C. Landers et al. ,Clinically ready magnetic microrobots for targeted therapies.Science390,710-715(2025).DOI:10.1126/science.adx1708