Researchers Sniff Out Perfumes with a Next-Generation Ultra-Slim "Electronic Nose" Sensor Design

Researchers from South Korea's Daegu Gyeongbuk Institute of Science and Technology (DGIST) have developed a next-generation "electronic nose," backed by artificial intelligence and inspired by the human olfactory system — yet small and light enough for use in wearable devices.

"The core innovation of our research is the ability to integrate multiple scent-sensitive sensors with diverse properties, similar to those of the human nose, into a single unit through a one-step selective laser fabrication process," explains project lead Hyuk-jun Kwon, professor in DGIST's Department of Electrical Engineering and Computer Science. "We are actively expanding development and commercialization efforts to apply this technology to personal healthcare, environmental pollution detection, and the fragrance industry."

The team's work was inspired by combinatorial coding, part of the human sense of smell in which a single molecule of a particular smell triggers multiple receptors — lighting up a unique pattern of neural signals key to distinguishing scents. The "electronic nose" created by the researchers works in the same way by generating distinct combinations of electrical signals, which are then fed to an artificial intelligence algorithm that can recognize and classify scents from the readings.

The nose itself is built by processing graphene under a laser, with a cerium oxide nano-catalyst forming a sensitive sensor array. The manufacturing approach is, the team claims, simpler than rival approaches, completable in a single step, and can be used to create integrated ultra-thin sensor arrays — meaning the sensors could be integrated into wearables or flexible patches. Each sensor can bend over 30,000 times without losing performance, the team found, and proved capable of identifying nine command perfume and cosmetic fragrances with over 95 percent accuracy.

"This study represents a significant advancement in the development of e-noses, demonstrating their potential for applications in traditional industries like environmental monitoring, food safety, and healthcare, as well as emerging fields such as fragrance marketing," the team concludes of its work. "The unique combination of simplified fabrication, tunable properties, and robust classification capability positions establishes the CeLIG [Ceria nanoparticle integrated Laser-Induced Graphene] e-nose as a promising tool for future sensor technologies."

The researchers' work has been published in the journal ACS Nano under open-access terms.