Meet the world's newest electronics manufacturers - Escherichia coli

Image credit: Daniel Mietchen, used under Creative Commons Attribution 2.0 Generic.

Image credit: Daniel Mietchen, used under Creative Commons Attribution 2.0 Generic.

Scientists at Duke University have harnessed the power of bacteria, E. coli in particular, to build a very small pressure sensor. 

According to a recent article published in Nature Biotechnology, reported by Ars Technica, the basic circuitry relies on the effects of encoded proteins on gene activity. A chemical feedback loop is formed that is dependent on the quantity of neighboring, similarly-engineered cells. 

The way it works is that bacteria are “printed” on a membrane using an inkjet printer. Varying pore sizes in the membranes allow the researchers to control the amount of nutrients administered, which in turn affects the size and shape of the bacterial colonies.

The end result (we’re skipping some steps for the sake of brevity) is that a linkage is established between specific protein antibodies and, in this use case, gold nanoparticles. This forms a tiny gold dome shape situated on its membrane – in other words, hardware built by bacteria. When two of the domes are placed opposite each other, pressure applied to the membranes allows them to make contact and establish a circuit. 

As the Ars Technica article points out, when compared to traditional manufacturing, scaling up is likely problematic for bacteria-engineered pressure sensors and circuitry. However, we’re wondering whether there is potential for building circuits in physical locations that are marginally accessible to humans and robots, but more easily accessible to bacteria. In healthcare, could this take the form of medical applications involving electrical impulses delivered to hard-to-reach areas, such as the brain or the heart?