Considering how technology is becoming smaller and smaller, and weighing up the need for devices to be adequately powered, researchers at the U.S. Office of Naval Research have been considering how bacteria can be used as conductors of electricity for small-scale electronic devices.
The genetically modified bacteria have been used to create electrical wires. The conducting wires are on the nano-scale, being a thousand times thinner than human hair. Not only are the bacteria efficient, they provide a relatively ‘green’ source of power. This is because the bacterial nanowires can be linked up to solar energy or other renewables, such as plant waste. In addition, the material of construction is biological and non-toxic (no chemicals are required to produce the nanoelectric components).
The microorganisms used are species of Geobacter. The organism naturally produces nanowires, which take the form of hair-like appendages that protrude from the bacterial cell. In the soil the organism uses the wires to connect with iron oxide and draws on the mineral to support growth.
The level of electricity produce in nature is insufficient to power a device. However, through altering the bacterial genetic make-up, which involves replacing amino acids, electrical conductivity can be boosted.
Through using tryptophan-infused nanowires the electricity produced increased 2000-fold. By packing thousands of bacterial nanowires together, sufficient power can be produced to run a small electronic device. A potential example is the integration of the nanowires with silicon chips.
Commenting on the research, Dr. Linda Chrisey, who works at the Naval Research center, said the research “could lead to the development of new electronic materials to meet the increasing demand for smaller, more powerful computing devices.”
The scientist further added: “Being able to produce extremely thin wires with sustainable materials has enormous potential application as components of electronic devices such as sensors, transistors and capacitors.”
The findings have yet to be published in a peer reviewed journal. Digital Journal has covered similar research. In June 2016 we profiled studies performed at the University of Massachusetts at Amherst, Holy Cross, and Brookhaven National Laboratory. Here scientists were using X-ray diffraction to determine the structure of the bacterial hairs. This revealed the hairs to have metallic-like conductivity, which can be utilized for bio-batteries.
