Scientists Develop Magnetic Microrobot to Deliver Drugs Inside the Body

Researchers at ETH Zurich have unveiled a groundbreaking microrobot capable of delivering medicine directly to affected areas within the human body using magnetic fields. This innovation, detailed in a recent study, offers promising applications in treating conditions such as strokes, infections, and cancer, with the potential to minimise side effects by targeting only the affected tissue.

The microrobot, a tiny spherical capsule, is composed of a dissolvable gel embedded with iron oxide nanoparticles, making it responsive to magnetic manipulation. Due to the extremely narrow blood vessels in the human brain, the capsule had to be both small and magnetically efficient—a technical challenge that the researchers successfully overcame.

To navigate the complex and fast-flowing vascular system, the team developed three different magnetic propulsion methods. These allow the robot to roll along vessel walls, move against blood flow, or steer through junctions. The robot can travel at speeds of up to 4mm per second—roughly equivalent to one inch every six seconds.

Once the microrobot reaches its destination, a high-frequency magnetic field is applied to heat and dissolve its outer shell, releasing the encapsulated medication precisely where it is needed. This method is particularly advantageous for minimally invasive procedures, as magnetic fields can penetrate deep into the body without harmful effects.

The technology has been tested in silicone models that simulate human and animal blood vessels, as well as in live trials involving pigs and the brain of a sheep. The next step for the ETH Zurich team is to begin clinical trials in humans, with the aim of bringing this technology into hospital operating theatres in the near future.

This innovation marks a significant step forward in targeted drug delivery and minimally invasive medical procedures, offering new hope for patients with hard-to-treat conditions.