Scientists create robot-like biomaterial with key traits of life
The DNA-based material can metabolise, self-assemble, and potentially even evolve
Like a page torn out of a science fiction novel, researchers at Cornell University created artificial materials out of DNA with incredible 'lifelike' abilities.
For the last 20 years, Prof. Dan Luo — a professor in the department of Biological and Environmental Engineering at Cornell University in Ithaca, New York — has been working to engineer DNA into materials that can be used for other purposes than that of life.
The gel-like material they created, is made up of long strands of DNA that propagate by growing on the front end and break down on the back end.
"The innovation of our material is that we afford metabolic activities into this material," said Prof. Luo in conversation with Quirks & Quarks host Bob McDonald, "which means they can both synthesize and degrade it."
They called the material DASH, which stands for DNA-based Assembly and Synthesis of Hierarchical materials.
We believe this has a great potential for material development, so you can have a material evolve into whatever features you want, hopefully.- Prof. Dan Luo, Cornell University
Prof. Luo carved tiny channels in a microfluidic chamber for the gel-like DNA material to travel through. Inside those channels, they carved other pillar-like obstacles for the biomaterial to move around.
By adding the building blocks and enzymes that can make new DNA to the front of the channels and enzymes to degrade it at the back, the material could move through its environment. As it moved through the channels it would assume specific shapes to navigate the pillars placed inside the channels.
Material exhibiting 'lifelike' traits
On top of showing artificial metabolic activity by building and breaking itself down, Prof. Luo said that developing a special shape is another characteristic trait of life.
The third lifelike trait is what he calls hierarchy assembly. "In other words, you have to build bigger things from smaller things" This is much the way we're assembled by starting with molecules, before moving up to cells, organs, tissues and then our body.
"[It's the] same concept here," said Prof. Luo. "We started with very, very small molecule, which is [the] so-called 'nucleotide' — those are [the] building blocks of DNA — and then they synthesize into DNA and then into [a] different shape."
"We believe this has a great potential for material development, so you can have a material evolve into whatever features you want, hopefully."
Detecting pathogens with this material
Prof. Luo said this material can also act like a biosensor to sense any kind of pathogenic DNA or RNA in a sample of blood or water.
They do this by adding a DNA strand to target the pathogen's genetic material with a specific colour indicator that will only grow and turn into that shade in the presence of the target in the sample.
"Once it's grows, it will grow into a shape we design [it] to."
Turning the material into protein factories
Prof. Luo said that another potential application for this material is to grow proteins without needing any live cells. DNA in nature is the template living systems use to build proteins based on the instructions coded into various genes.
He said that currently, some of the top ten drugs sold in the world are based on proteins, which are scientists produce from living cells, which can be "very finicky."
"They are prone to contamination and cost a lot," added Prof. Luo.
To build a protein, Prof. Luo adds a template DNA sequence to code for the protein they want. By adding the building blocks and enzymes responsible for making proteins, "you just shake and bake. In probably one hour or two, you get your proteins."