Sniffing out danger

In the heart of UC Irvine's engineering complex, scientists are working on a device that appeals to the senses: an electronic nose capable of detecting explosives, narcotics, dangerous chemicals and more - down to individual molecules.

Led by Peter Burke, a professor in electrical engineering and computer science, the team aims to fuse nature's olfactory precision with nanoscale electronics. The goal? A device that reacts to trace amounts of chemical substances - even those that differ by just a single carbon atom.

The objective is to create a handheld device that can instantly detect TNT residue at a crime scene, identify harmful airborne chemicals after an industrial spill or sniff out illicit drugs before they enter the postal system. This electronic nose promises unmatched sensitivity and specificity, potentially transforming fields like public safety, manufacturing, environmental protection and even medical diagnostics.

Three technologies, one nose

The key to the project's success lies in integrating three complementary advances:

1. Fused olfactory receptor-ion channel proteins - these genetically engineered proteins trigger an electrical response when an odor molecule binds
2. Nanowire sensing - derived from Burke's lab, this technology picks up the minute electrical changes generated when a single ion channel opens.
3. Lipid bilayer-nanotube tethering chemistry - this innovation securely attaches the sensing proteins to nanostructures capable of transmitting electrical signals.

"The combination of these three technological advances and the result of millions of years of the evolution of olfactory receptor proteins is enabling the goal of single-molecule sensing with specificity towards analytes that differ by as little as one carbon atom," Burke says.

From lab to real-world impact

In March 2022, the National Science Foundation awarded Burke and his collaborator Francesco Tombola a $450,000 grant to support this initiative, enabling strides toward ultra-sensitive chemical sensors used in security, disaster response, and environmental monitoring. The approach is still conceptual but already patented and laying the groundwork for future "massively parallel" sensor arrays - chips with hundreds of distinct odor-detecting elements.

As part of the regional I-Corps program at UC Irvine, Sangjun Noh, a Ph.D. candidate in Burke's lab, took the electronic nose project beyond the lab to explore its real-world impact.

Through more than 12 customer discovery interviews with researchers, lab managers and safety officers, he identified a strong need for real-time chemical sensing to enhance laboratory safety and prevent contamination. These insights also revealed potential national security applications, such as detecting explosives and hazardous chemicals. The I-Corps experience not only validated the importance of the technology but also helped the team refine its vision to align with urgent societal challenges.

Why it matters

Imagine a handheld device that can instantly detect TNT residue at a crime scene, identify harmful airborne chemicals after an industrial spill, or sniff out illicit drugs before they enter the postal system. This electronic nose promises unmatched sensitivity and specificity, potentially transforming fields like public safety, manufacturing, environmental protection and even medical diagnostics.

Though promising, the technology must move from proof-of-concept to robust, deployable systems. This means tackling challenges like integrating many sensors on one chip, ensuring stability under real-world conditions, and making the devices affordable and scalable.

But with dual expertise in nanotechnology and electrophysiology, Burke's lab is poised to bridge biology and engineering in ways few others can.

This project not only showcases cutting-edge science - it taps into deep evolutionary design. By harnessing refined biological receptors and fusing them to advanced electronics, the engineers at UC Irvine are laying the foundation for a technological leap: giving human-made systems the ability to "smell" the world with unparalleled precision.

Generative AI assisted in the writing of this story.