High-Sensitivity Zinc-Based Surface Plasmon Resonance Biosensor for SARS-CoV-2 Detection Using Kretschmann Configuration

The virus that causes COVID-19, severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), infects the body by latching onto Angiotensin-Converting Enzyme 2 (ACE2) receptors, primarily in the lungs, triggering inflammation, pneumonia, and breathing problems. The virus can also damage other organs, including the heart, kidneys, and brain, resulting in complications like blood clots and organ damage. In extreme cases, an overactive immune reaction, called a cytokine storm, can amplify tissue and organ damage. For that, five different structures, using the defined layers, are studied in this work to compare the performance and to study how the COVID-19 virus influences the SPR sensor proposed. Using the angular interrogation method, we numerically evaluate the performance at the wavelength of 633 nm. This study demonstrates a new sulfide material-based structure for SARS-CoV-2 detection using a prism-based SPR nano-biosensor. In which case, this is a designed configuration inspired by the Kretschmann configuration, silver, zinc telluride, zinc sulfide layer, 2D materials of black phosphorus and graphene, and a sensing medium that takes advantage of surface plasmon excitations and evanescent waves. Through the analysis of SARS-CoV-2 samples, the proposed structure reached a maximum sensitivity of 474.08°/RIU, a QF of 131.00 RIU⁻¹, and a DA of 0.6550, which is a significant improvement over the existing methods.