MIT engineers have coaxed bacterial cells to produce biofilms that can incorporate nonliving materials, such as gold nanoparticles and quantum dots. These “living materials” combine the advantages of live cells — which respond to their environment, produce complex biological molecules, and span multiple length scales — with the benefits of nonliving materials, which add functions such as conducting electricity or emitting light.
This approach could one day be used to design more complex devices such as solar cells, self-healing materials, or diagnostic sensors, says Timothy Lu, an MIT assistant professor of electrical engineering and biological engineering. Lu is the senior author of a paper describing this innovation in the March 23 issue of Nature Materials. The researchers also demonstrated that the cells can even coordinate with each other to control the composition of the biofilm. These hybrid materials could be worth exploring for use in energy applications such as batteries and solar cells, Lu says. The researchers are also interested in coating the biofilms with enzymes that catalyze the breakdown of cellulose, which could be useful for converting agricultural waste to biofuels. Other potential applications include diagnostic devices and scaffolds for tissue engineering.