Abstract
Early detection of COVID-19 and new variants is important to control widespread outbreak. In this study, we proposed a dual-clamped SERS based SARS-CoV-2 biosensor using microstructured digital versatile disc (DVD) as substrate and modified silver nanoparticles as SERS nanotags for detection of Omicron variant using a portable Raman spectrometer. This SERS based biosensor displayed a detection limit of 50 pg/ml for both SARS-CoV-2 spike proteins - Beta and Omicron variants, providing a Ct value range of 30-32, better than rapid antigen tests usually ranging from 25-28, and can be used for rapid and sensitive detection for large scale group testing needs.