Fig. 5.

Schematic diagram of the five-layered (Bk7/Au/PtSe₂/Graphene/ PBS) SPR biosensor for examination of SARS-CoV-2 produced virus; the SARS-CoV-2 virus can be detected using three modes of operation: (a) human mAbs immobilised on a viral spike RBD allow for fast detection of the whole virus spike (spike RBD as analyte and mAbs as ligand), (b) fast mAbs recognition using immobilized virus spike RBD (mAbs as analyte and spike RBD as ligand), and (c) viral RNA sequence detection on the graphene-implanted sensor surface with immobilised probe sequences [55].