Scientists at the Stuttgart-based Max Planck Institute for Intelligent Systems (MPI-IS) have developed a microrobot that theoretically can deliver drugs to specific locations in the human body via the circulatory system. To date, the engineers have tested the “microroller” – a microrobot shaped like a ball – only in a laboratory settings. The team’s goal is to further develop the device as a means of performing minimally invasive disease treatment.

The microroller is made of glass microparticles and is approximately the size of a white blood cell. One half of the robot’s surface is a magnetic nanofilm. The other side consists of anti-cancer drugs. Operators use imagery-guided remote magnetism to control the robot’s movement through the circulatory system. The microroller is just under 8 micrometers in diameter and can travel up to 600 micrometers per second. The magnetic propulsion system has proved it can operate successfully through high-speed simulated blood flow in lab tests. The MPI-IS microrobots can also identify specific cells of interest using “cell-specific antibodies on their surface.” When the robot reaches the target cells, it releases the drug molecules.

Further development is needed before the MPI-IS scientists can begin testing in humans. Challenges that remain include proving that the microrobots can navigate a living animal’s circulatory system. Current clinical imaging machinery does not have sufficient resolution to guide microrobots that small through blood vessels. Also, the size of the anti-cancer drug payload is so tiny that thousands of microrobots would need to be sent and controlled in a swarm to deliver a sufficient quantity of the drugs.

The prospect of microrobot technology is one of the most exciting ideas we’ve encountered. The tech may sound like it comes from a Disney movie, but as scientists overcome the development challenges, the concept of cell-specific treatment within the body without surgery could make a huge difference in patients’ lives.