Scientists create "xenobots" using living cells

A team of scientists from the University of Vermont working with researchers from other institutions, has been able to repurpose living cells. The cells used were scraped from Frog embryos and assembled into new lifeforms. The new lifeforms are millimeter-wide "xenobots" that can move towards a target. They may also be able to pick up a payload, such as a medication, that needs to be delivered to a specific place inside the person. The xenobots can also heal themselves after being cut.

Researchers say that they are novel living machines that are neither a traditional robot or a known species of animal. They are described as a new class of artifact that is a living, programmable organism. The creatures were designed on a supercomputer at UVM and assembled and tested by biologists at Tufts University.

The robots have multiple uses, including finding radioactive contamination and gathering microplastic in the ocean. They might also travel in arteries to scrape out plaque. This research marks the first time that biological machines were designed completely from the ground up. The team used an evolutionary algorithm to create thousands of candidate designs.

The computer would try and achieve a task assigned by scientists, such as locomotion in one direction, and the computer would assemble cells over and over to perform the job. The computer was driven by basic rules about the biophysics of what a single frog skin or cardiac cells can do.

The most promising designs churned out by the computer were selected for testing. The cells were harvested from embryos of an African frog species called Xenopus laevis, which is where the xenobots name comes from. The cells were joined under a microscope into an approximation of the designs specified by the computer. The resulting organisms could move in a coherent fashion and explore their environment for days or weeks using embryonic energy stores. The bots are also biodegradable; when their job is done, they are just skin cells.