COVID-19 diagnostics: direct optical detection of viruses and antigens with nanofabricated surfaces

Stanford researchers at the Dionne Lab have developed a new hand-held technology that uses optical characterization to rapidly and quantitatively measure extracted viral-RNA target binding or antibody binding to nanofabricated platforms. Importantly, this invention can detect extracted viral-RNA gene sequences from the SARS-CoV-2 genome encoding for different proteins, including envelope proteins, RNA-dependent RNA polymerase, and proteins that form viral nucleocapsids simultaneously and without amplification. We can also detect antibodies, including IgG, IgM, and IgA from serological samples. This technology could be readily extended to other viral or bacterial infections.

The platform relies on high-quality-factor (high Q) nanostructured dielectric substrates, known as metasurfaces. By relying on free-space resonant metasurfaces, this invention overcomes the typically low signal-to-noise ratio of lateral flow assays. Consisting of hundreds or thousands of independent and highly environment sensitive image pixels, each metasurface facilitates an unprecedented number of simultaneous measurements to be performed at cutting edge detection limits using off-the-shelf consumer electronics-grade camera sensors. Using the nanopatterned Si surfaces also guarantees the scalability and cost-effectiveness of this assay, by using well-established CMOS fabrication processes. Additionally, unlike fluorescent-based assays, this platform does not suffer from bleaching or photoblinking. These optically resonant substrates will allow measurement of antigen binding at the point-of-care within an hour. Clinicians can detect multiple nucleic acid sequences on a single chip for assay multiplexing, improving sensitivity and specificity, and enabling detection of multiple viruses simultaneously.

Stage of Development