ETH Zurich researchers developed a drug-carrying microrobot that combines magnetic steering, X-ray visibility and triggered drug release in a dissolvable capsule. Iron oxide nanoparticles provide magnetic control, while tantalum particles make the capsule visible during navigation. A catheter releases it near the target, and an external electromagnetic system guides it through vessels or cerebrospinal fluid.
The preclinical work combined rolling along vessel walls, pulling with magnetic gradients and using blood flow to steer through junctions. Researchers dissolved a clot in a realistic vessel model, demonstrated all three navigation modes in pigs and guided capsules through a sheep's cerebrospinal fluid. A high-frequency magnetic field heats the particles to dissolve the gel and release the payload. The integrated system, reported in Science, brings delivery, imaging and control together in a platform designed for further clinical development.
