“…177 Applied functional nanomaterials binding with receptors are designed and fabricated in a wide range, such as metal nanoparticles (gold nanoparticles, AuNPs), [178][179][180] carbon materials (nanotubes, 181 graphene 182 ), quantum dots (QDs), 183 polymer materials, 184 and other unique nanomaterials. 185 Receptors immobilized on the nanomaterials, such as nucleic acids, 186 antigens, 187 aptamers, 188,189 antibodies, 190 and other biological or synthetic molecules serve as the recognition elements for the targets with certain affinities and specifications. 191 When it comes to the detection of HCoVs, such as SARS-CoV, 192 the Middle East respiratory syndrome coronavirus (MERS-CoV) 193 and SARS-CoV-2 194 that caused epidemics or pandemics, various transducers based on different principles can be applied in the biological and medical fields, including electrochemical, fluorescence-based or colorimetric biosensors, [195][196][197][198][199] localized surface plasmon resonance (LSPR), [200][201][202] surface-enhanced Raman scattering (SERS), [203][204][205] quartz crystal microbalance (QCM) sensors, 206,207 piezoelectric sensors, 208 and other kinds of biosensors.…”