A group of engineers at Cornell University have constructed a new type of biomaterial using artificial DNA as its base. Their approach has given the material a number of lifelike properties, such as a metabolism and the ability to self-assemble and self-organize.
The artificial metabolism is particularly interesting. The material was programmed to move and this was powered by its metabolism. As reported in Science Robotics, the material can autonomously grow and decay. It was created using DASH (DNA-based Assembly and Synthesis of Hierarchical) materials.
“We are introducing a brand-new, lifelike material concept powered by its very own artificial metabolism," senior author Dan Luo, professor of biological and environmental engineering, said in a statement. "We are not making something that’s alive, but we are creating materials that are much more lifelike than have ever been seen before.”
The material is equipped with DNA instructions that give it its metabolism and allow it to regenerate autonomously. The material began its life as nanoscale building blocks in a reaction solution. It then arranged itself into polymer strands which then formed shapes measuring just a few millimeters in length. The reaction solution was then injected with a microfluidic device, which provided a liquid flow of energy and the right building blocks for biosynthesis (the production of complex molecules in living things) to occur.
At that point, the researchers witnessed the material growing at the end facing the flow of energy and degrading at the other. This growth and degradation allowed the material to move forward against the flow in a way reminiscent of how slime molds move. The team was then able to make different sets of the material compete against each other in a race. The winners and losers were decided by the randomness of the system rather than by intrinsic advantages of particular shapes.
“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,” lead author Shogo Hamada, lecturer and research associate in Cornell's Luo lab, explained. “Even from a simple design, we were able to create sophisticated behaviors like racing. Artificial metabolism could open a new frontier in robotics.”
The team is now interested in creating a material that can respond to stimuli like light and perhaps even detect danger. The use of synthetic DNA means there's a possibility that the material will self-evolve, creating better and better versions of itself. The approach could be employed to detect pathogens, create new nanomaterials, produce proteins, and maybe even act as a base for biocomputers.
John Munson/Cornell University