A team of MIT engineers have created ‘living cells’ made from bacteria that could be used to ‘grow’ electronic devices. The cells are then used to produce biofilms that incorporate nonliving materials, such as gold nanoparticles and quantum dots. The resulting ‘living materials’ could produce complex biological molecules, which could be utilised in solar cells, self-healing materials, diagnostic sensors and even smartphones.
“Our idea is to put the living and the nonliving worlds together to make hybrid materials that have living cells in them and are functional,” Timothy Lu, an assistant professor of electrical and biological engineering, said of the team’s discovery. “It’s an interesting way of thinking about materials synthesis, which is very different from what people do now, which is usually a top-down approach.”
The bacterial cells used included E. coli, because it naturally produces biofilms that contain so-called “curli fibers” that allow it to attach itself to surfaces.
By programming cells to produce different types of curli fibers under certain conditions, the researchers were able to control the biofilms’ properties and create gold nanowires, conducting biofilms, and films studded with quantum dots, or tiny crystals that exhibit quantum mechanical properties. Cells were also engineered so they could communicate with each other and change the composition of the biofilm over time.
By creating cells that essentially ‘talk to each other’, there is every possibility that gadgets could one day be grown.
“Ultimately, we hope to emulate how natural systems, like bone, form. No one tells bone what to do, but it generates a material in response to environmental signals.”
Lead image via MIT/liewcf