At-Home Test Spots Disease With Startling Accuracy

New tech combines coffee rings, AI for rapid, sensitive results.

Suffering from a sore throat or sniffles? While rapid at-home tests offer convenience, their sensitivity can be lacking. Now, a new biosensing technology promises to increase the accuracy of rapid at-home diagnostics, potentially detecting viruses like COVID-19 with much greater precision.

Combining Coffee Rings and Nanoparticles

The innovative test, developed by researchers at the **University of California, Berkeley**, leverages the “coffee-ring effect,” a natural evaporation process where particles concentrate at the edge of a drying droplet. It combines this with plasmonics and artificial intelligence to identify disease biomarkers rapidly.

Kamyar Behrouzi, who recently earned a Ph.D. from **UC Berkeley**, noted, “This simple yet effective technique can offer highly accurate results in a fraction of the time compared to traditional diagnostic methods.” He added that the technology paves the way for more affordable, accessible diagnostics, especially in low-resource settings.”

How It Works

The technology uses plasmonic nanoparticles, which uniquely interact with light. A user adds a liquid droplet, such as a nasal swab, to a membrane. As the droplet dries, disease biomarkers concentrate. A second droplet, containing nanoparticles engineered to attach to these biomarkers, is added. If biomarkers are present, the nanoparticles form patterns that alter light interaction. These changes can be observed or analyzed via an AI-powered smartphone app.

Results are available in under 12 minutes, with COVID-19 detection being up to 100 times more sensitive than existing tests.

Potential for Sepsis Detection

According to the CDC, sepsis affects at least 1.7 million adults in the U.S. annually and contributes to nearly 350,000 deaths. (CDC.gov)

“One of the key proteins that we are able to detect with this method is a biomarker of sepsis, a life-threatening inflammatory response to a bacterial infection that can develop rapidly in people over 50. Every hour is critical, but culturing bacteria to determine the source of the infection can take a few days. Our technique could help doctors detect sepsis in 10 to 15 minutes.”

—Liwei Lin, Study Senior Author, Distinguished Professor of Mechanical Engineering at UC Berkeley

The research team has already produced a prototype of a home testing kit that is similar to current at-home COVID tests.

Lin hopes that our technology makes it easier and more accessible for people to regularly screen for conditions like prostate cancer without leaving the home.”

Additional co-authors of the study include **Zahra Khodabakhshi Fard**, **Chun-Ming Chen**, **Peisheng He** and **Megan Teng** of **UC Berkeley**.