Researchers at the University of Colorado Boulder have developed a “living” construction material made of microbes that may be able to repair itself, reproduce and even pull carbon dioxide out of the air. Regular concrete is a major contributor to greenhouse gas emissions according to Dr. Wil Srubar, who heads up the research team.
These specialized living building materials, or “LBMs,” are made from cyanobacteria mixed into a “scaffold” of gelatin and sand. Provided with the right light and other conditions, the microbes absorb carbon dioxide and in turn make calcium carbonate, which is the main ingredient in cement. Researchers at the Living Materials Laboratory mold the mix into varying shapes, ranging in size from small two-inch cubes to shoebox sized bricks and even larger structures. The material is durable and has about the same strength as cement-based mortar used by contractors today, although the material is weaker than conventional concrete. Still, the researchers were able to stand on the two-inch cubes without them breaking, Dr. Srubar said.
The material is also capable of regeneration—a brick cut in half is capable of growing three new generations of blocks, or eight “descendant” blocks.
A building material capable of healing its own cracks would be highly valuable in extreme climates, following damage caused by natural disasters and in the construction of military structures. The bricks also could be molded to change color to indicate dangerous toxins and potentially eliminate them.
Dr. Srubar says that the plan is to continue to optimize the material’s formula and explore other ways that living organisms could improve the living bricks. Since bacteria often grows at exponential rates, there is a lot of potential to use the living bricks for projects in outer space or resource-scarce environments, such as deserts or the Arctic. “There’s no way we’re going to carry building materials to space, so we’ll bring biology with us,” Dr. Srubar said.
The doctor also acknowledged that although his team is at the beginning stages of research, he expects the material to be commercially available within the next five to 10 years when issues such as long-term viability have been solved.
The Living Materials Laboratory is supported by the Defense Advanced Research Projects Agency. For more information, visit Dr. Srubar’s Living Materials Laboratory.
Read the team’s scholarly article, “Biomineralization and Successive Regeneration of Engineered Living Building Materials.”
Read more in the New York Times article, “Bricks Alive! Scientists Create Living Concrete.”