A study of highly sensitive surface plasmon resonance biosensor for the detection of SARS-CoV-2 virus

The severe acute respiratory syndrome caused by coronavirus-2 (SARS-CoV-2) is recognized as a worldwide health issue in the coronavirus disease (COVID-19) pandemic. The development of highly selective and sensitive biosensor probes for the detection of coronavirus is one of the essential requirements to prevent the disease. DNA-based surface plasmon resonance (SPR) biosensor plays a vital role in the highly selective and sensitive detection of SARS-CoV-2. In this work, we design a multilayer structure of SPR biosensor for rapid detection of the SARS-CoV-2 by using black phosphorous (BP), bismuth ferrite (BiFeO₃), and thiol-tethered ssDNA. Herein, three distinct SPR biosensor structures i.e. BK-7 Prism-Ag-BiFeO₃-ssDNA (ST-I), BK-7 Prism-Ag-BP-ssDNA (ST-II), and BK-7 Prism-Ag-BiFeO₃-BP-ssDNA (ST-III) are used to identify SARS-CoV-2. Thiol-tethered ssDNA works as a ligand for selective detection of coronavirus. The multilayer structure of SPR biosensors is analyzed using the transfer matrix method (TMM). It is found that ST-III shows maximum sensitivity (356.19°/RIU), detection accuracy (2.57), quality factor (122.40 RIU^− 1), and limit of detection (1.40 × 10^–5). This work may lead to the development of highly sensitive SPR biosensors for the rapid and label-free detection of SARS-CoV-2.