Watch how Berkeley research turned coffee spills into a life-saving test

Have you ever looked closely at what happens to spilled coffee as it dries? That’s what inspired a UC Berkeley engineering PhD candidate to create a breakthrough in medical testing. Watch this short video –– part of our ongoing series called Born at UC Berkeley –– to learn more about the innovation from our student host, Angela Zhang.

Kamyar Behrouzi, now graduated, developed the rapid diagnostic test based on the “coffee-ring effect,” the pattern formed when spilled coffee dries and particles then migrate to the outer edge. The same physical principle can be used to concentrate disease markers, making them easier to detect.

Instead of coffee, users apply a swab sample to a membrane, where particles naturally gather into a ring as the liquid dries. A solution containing plasmonic nanoparticles is then added. If disease biomarkers are present, the nanoparticles bind to them, creating visible patterns that alter how light interacts with the membrane.

The test can deliver results in as little as 12 minutes and has shown accuracy far exceeding that of existing rapid COVID-19 tests. Researchers say the method could be adapted to detect sepsis, COVID-19, influenza and even certain cancers.

The innovation is another example of how fundamental science can lead to practical, potentially life-saving technologies born at UC Berkeley. Read more about the discovery here, and follow UC Berkeley on Instagram, YouTube and other social platforms to see more videos like this.