Design and Modelling of Surface Plasmon Resonance Biosensor Employing BaTiO₃ and Graphene Nanostructure for Detection of SARS-CoV-2 Virus

The present article exhibits a comprehensive analysis of surface plasmon resonance (SPR)-based biosensor for real-time and label-free detection of the novel SARS-CoV-2 virus. The proposed SPR sensor is based on the Kretschmann geometry, which is designed by using CaF₂ prism, titanium oxide (Ti0₂), Silver (Ag), barium titanate (BaTiO₃), graphene, and thiol-tethered ssDNA layer as a ligand for the SARS-CoV-2 virus. The transfer matrix method is employed to investigate the angular reflectance characteristics. The thickness of different layers and the number of layers are judiciously optimized. The enhancement in the sensitivity of the proposed sensor is studied by considering different arrangements of the layers. It is revealed that with a monolayer of BaTiO₃ and bilayer of graphene, the sensor bestows an optimum sensitivity of 433.63 deg./RIU, figure of merit of 136.79 1/RIU, detection accuracy of 0.331 \({Deg.}^{-1}\) ${Deg.}^{-1}$ , and detection limit in the order of \({10}^{-5}\) ${10}^{-5}$ . Apart from this, electric field enhancement factor is studied for different concentration of SARS-CoV-2 virus. The notable sensing performances indicate that the proposed SPR sensor can be a potential candidate to pave a new path for detecting SARS-CoV-2, based on the hybrid materials.