DOE funds Saraf’s work to engineer electronic interface between living cell and nanodevice

Dr. Ravi Saraf, UNL’s Lowell E. & Betty Anderson Professor of Engineering, received a grant of nearly $1 million from the U.S. Department of Energy’s Office of Basic Sciences for a three-year research project.

Saraf and his team with the Department of Chemical & Biomolecular Engineering in the College of Engineering will develop bio-nano hybrid systems based on chemical reaction in living cells.

“Each cell is a miniature chemical reactor,” Saraf said, describing how electrons shuttle from one molecule to another in a process called redox. “The question is, ‘Can we use this electron production to flip a switch in an electronic device, on or off, similar to a transistor?’”

A transistor typically involves thousands of electrons, but Saraf has developed specialized devices that can sense a single electron while functioning at room temperature, instead of previously-observed lower temperatures where cells will cease to function.

Another challenge was size incompatibility between cell and device, with a cell (measured in microns) typically 1,000 times bigger than an electron (measured in nanometers).

“We made a nanoparticle-based device that is as large as a cell and operates at room temperature,” Saraf said, “and we have shown that the cell can turn this device on and off when it is fed nutrient.” He will continue to focus on cells’ metabolic activity, regulating their exposure to a food source to ultimately build “smart sensors” that respond to specific chemicals.

Saraf said this work applies to both microorganisms and mammalian cells for driving nanostructured devices, and “will represent a new paradigm of hybrid bio-nano devices” involving a broad range of high-impact applications with the potential for inexpensive manufacturing.

Applying this research with living cells in the human body can reveal how drugs affect cells, to predict how cells will respond, Saraf said. Another example could be a microorganism as an intelligent and adaptable “driver” that is sensitive to detect agents, such as anthrax. He added that it may be possible to extend the idea to directly convert food for the microorganism into electricity.