Robots vs. Humans: Scientists Create Machines That Mimic Biological Life

They’re hailing their breakthrough as “creation,” and it might be so. Engineers at Cornell University claim they’ve “created” simple machines constructed of biomaterials with the properties of living things.

In short, what they’ve created are living machines that mimic biological life as we know it. Cornell engineers, however, refuse to say their creation is “alive” in the conventional sense.

Instead, they say the material they’ve created has the necessary traits for life. The machine also contains instructions for metabolism and regeneration.

The material the team created can last for only two cycles of synthesis and degradation before it expires or dies. Longevity can likely be extended. This will open the possibility for more “generations” of the material as it self-replicates.

“Ultimately, the system may lead to lifelike self-reproducing machines,” Shogo Hamada, lecturer and research associate in the Luo lab and lead and co-corresponding author of the paper, said.

Exploiting the fact DNA is a polymer, the geniuses at Cornell used a technique they call DASH (DNA-based Assembly and Synthesis of Hierarchical) materials to construct a DNA material with capabilities of metabolism, self-assembly and organization, which are the three key traits of life. Think of an amoeba to picture life in its simplest form.

“We are introducing a brand-new, lifelike material concept powered by its very own artificial metabolism,” Dan Luo, professor of biological and environmental engineering at the College of Agriculture and Life Sciences, said.

“We are not making something that’s alive, but we are creating materials that are much more lifelike than have ever been seen before.”

In nature, DNA molecules are synthesized and assembled into patterns in a hierarchical way, resulting in something that can perpetuate a dynamic, autonomous process of growth and decay. But by using DASH, Cornell engineers created a biomaterial that can autonomously emerge from its nanoscale building blocks and arrange itself — first into polymers and eventually mesoscale or larger shapes.

Starting from a 55-nucleotide base seed sequence, the DNA molecules were multiplied hundreds of thousands times, creating chains of repeating DNA a few millimeters in size. The reaction solution was then injected in a microfluidic device that provided a liquid flow of energy and the necessary building blocks for biosynthesis.

With the solution, the DNA synthesized its own new strands with the front end of the material growing and the tail end degrading in optimized balance. It thereby made its own locomotion, creeping forward, against the flow, in a way similar to how slime molds move.

The locomotive ability allowed researchers to pit sets of the material against one another in competitive races. Due to randomness in the environment, one body wlll eventually gain an advantage over the other, allowing one to cross a finish line first.

“The designs are still primitive, but they showed a new route to create dynamic machines from biomolecules. We are at a first step of building lifelike robots by artificial metabolism,” Hamada said.

He added that even from a simple design, they were able to create sophisticated behaviors like racing. He noted that artificial metabolism might open a new frontier in robotics.

The engineers are currently exploring ways to have the material recognize stimuli. They also want the material to autonomously be able to seek out stimuli in the case of light or food or avoid it if it’s harmful.

The key innovation is the programmed metabolism embedded into DNA materials. The DNA contains the set of instructions for metabolism and autonomous regeneration. After that, it’s on its own.

“Everything from its ability to move and compete, all those processes are self-contained. There’s no external interference,” Luo said. “Life began billions of years from perhaps just a few kinds of molecules. This might be the same.”

“More excitingly, the use of DNA gives the whole system a self-evolutionary possibility,” said Luo. “That is huge.”

The paper, entitled “Dynamic DNA Material With Emergent Locomotion Behavior Powered by Artificial Metabolism,” was published April 10 in Science Robotics.