Scientists have built a microbot out of algae which could swim through the body – propelled by magnetic forces – and potentially destroy cancer cells when it decomposes.

The idea is that the miniature robots could help doctors to deliver drugs and diagnose diseases in a non-invasive manner.

The spirulina algae, better known for its properties as a “superfood”, has had magnetic particles added to it so that its movement can be controlled remotely, while its natural fluorescent glow makes it easy to track.

Image: Multifunctional biohybrid magnetite microrobots for imaging-guided therapy/Science Robotics

Furthermore, spirulina appears to be toxic to cancer cells. In a laboratory experiment, about 90% of cancer cells were destroyed after tumour cells were exposed to the spirulina for 48 hours.

The algae robots have so far only been used in the stomachs of rats, and rigorous testing is needed to check that they degrade without causing harm to the human body.

The application of nanotechnology in medicine has been exciting scientists for some time. Developing nanobots that can be programmed to find and destroy cells, deliver drugs or perform surgery from inside our bodies has the potential to lead to new types of treatment.

“Creating robotic systems which can be propelled and guided in the body has been and still is a holy grail in the field of delivery system engineering,” said nanomedicine researcher Professor Kostas Kostarelos, a team member who worked on the research told the Independent.

Spirulina algae is looking like one possible solution to the problem many scientists are trying to solve.