Assistant Professor Yuanwei Li has received a DARPA grant to develop a nanophotonic chip-based sensor array capable of detecting and tracking neurochemical biomarkers in real time with unprecedented sensitivity and throughput. If successful, the technology could pave the way for portable, wearable devices that continuously monitor brain chemistry, enabling earlier detection of neurological conditions and more personalized diagnostics.
Written by Jackson Brunner
Assistant Professor Yuanwei Li of the Department of Materials Science and Engineering at The Grainger College of Engineering will develop nanophotonic sensor arrays on chips with the goal of tracking neurochemical biomarkers in real time.
Why it matters: Current biosensing technologies struggle to detect low-abundance molecules that carry critical health signals. Li's nanophotonic chip aims to break through fundamental trade-offs between sensitivity, speed and scalability — potentially enabling real-time monitoring of brain chemistry.
Pictured: Assistant Professor Yuanwei Li
The big picture: Li, who joined the department in January 2026, received the DARPA grant to develop scalable hybrid nanophotonic sensor arrays for high-throughput neurochemical biomarker detection.
“We’re essentially building a chip that can listen to the brain’s molecular language,” Li said. “By capturing these fleeting chemical signals in real time, we hope to unlock new windows into brain health that were previously invisible.”
How it works: The platform translates biomolecule binding events into quantitative optical signatures that can be read across many sensors simultaneously.
The CMOS-compatible nanophotonic sensor array sits on a chip designed for parallel, high-throughput detection.
Each sensor converts biomolecule binding into a distinct optical signal that reveals both presence and concentration.
The scalable architecture enables tracking of multiple neurochemical biomarkers simultaneously.
The challenge: Neurochemical biomarkers are often low in abundance and fluctuate rapidly over time, making them difficult to capture with existing technologies. Current biosensing approaches face fundamental trade-offs: high sensitivity often comes at the cost of throughput, and scalable platforms may sacrifice detection limits.
What's next: If successful, the technology could enable new approaches to monitoring neurochemical biomarkers over extended periods. The long-term vision is a portable, potentially wearable platform that provides continuous insight into brain chemistry dynamics. Such a device could support earlier detection of neurological conditions and enable more personalized diagnostic approaches.
The bottom line: Li’s nanophotonic platform aims to make high-sensitivity biosensing scalable and practical for tracking the dynamic molecular signals that govern brain health.