Title: Surface-Enhanced Raman spectroscopy (SERS) for characterization SARS-CoV-2

Abstract

I n this research we used SERS with silver nanoparticles (AgNPs) as the active substrate to develop a, simple, quick, and accurate method for the detection and characterization SARS-CoV-2 without the need for RNA isolation and purification. Inactivated SARS-CoV-2 was used. The SERS signals were more than 105 times enhanced than the normal Raman (NR) spectra. The SERS spectra of SARS-CoV-2 fingerprint revealed pronounced intensity signals of nucleic acids; aromatic amino acid side chains: 1007 cm-1 (Phe marker), 1095 cm-1 (CN and PO2- markers), 1580 cm-1 (Tyr, Trp markers). Vibrations of the protein main chain: 1144 cm-1 (CN and NH2 markers), 1221 cm-1 (CN and NH markers), 1270 cm-1 (NH2 marker), 1453 cm-1 (CHCH2 marker). All of these biomolecules could be adsorbed on the AgNPs surface's dense hot patches. The intensity of the SERS band varied with the concentration of SARS-CoV-2, with a virus detection limit of less than 103 vp/mL and RSDs of 20%.