Xenobots are less than a millimetre (0.04 inches wide) and are assembled from cells taken from the African clawed frog  – Xenopus laevis – from which they get their name.

Scientists first used the Deep Green supercomputer cluster at the University of Vermont to create an algorithm that assembled a few hundred virtual skin and heart cells into a myriad forms and body shapes, for specific tasks. 

Xenobots could help clear arteries

Based on the blueprints, a team of biologists gathered stem cells, harvested from the embryos of the African frogs and used tiny forceps and a miniature electric knife to cut and join the cells under a microscope into a close approximation of the designs specified by the computer.

Once assembled into forms never seen in nature, the cells began to work together. The skin cells formed a “body” while contracting heart muscle cells were repurposed to create a forward motion, allowing the robots to move on their own.

Researchers are hopeful the xenobots could one day be programmed to move through arteries scraping away plaque, or swim through oceans removing toxic microplastic.

And now it is proven they can replicate, they could repair themselves if damaged or torn, scientists hope. 

The research was published in the journal PNAS.