Table 2.

Biosensors for coronaviruses-specific RNA detection

Coronavirus subgroup	Analyte	Assay method	Detection time	Concentration range	Limit of detection	Tested sample	Reference
SARS-CoV	Oligonucleotide	Electrochemical (SWV)	2 h 10 min	0.01–1.01 nM	6 pM	Spiked oligonucleotide solutions	[100]
SARS-CoV	Oligonucleotide	Electrochemical (CA)	3 h 25 min	–	8 pM	Spiked oligonucleotide solutions	[102]
		Electrochemical (CV)	1 h 30 min		0.5 nM
SARS-CoV	Oligonucleotide	Electrochemical (CV)	2 h 20 min	2.5–50 pM	2.5 pM	Spiked oligonucleotide solutions	[101]
SARS-CoV	Oligonucleotide	Electrochemical (SWV)	3 h	0.1–10 nM	–	Spiked oligonucleotide solutions	[103]
SARS-CoV	Oligonucleotide	Optical (colorimetry)	5 min	–	< 100 fmol	Spiked oligonucleotide solutions	[107]
SARS-CoV	RNA	Optical (SPR)	~ 2 h	–	2 nM	Throat swab samples	[37]
MERS-CoV	RNA	Optical (fluorescence)	30 min	–	0.1 pM	Pseudo-serum samples	[104]
MERS-CoV	Oligonucleotide	Optical (colorimetry)	–	20–1000 nM	1.53 nM	Spiked oligonucleotide solutions	[106]
MERS-CoV	Oligonucleotide	Optical (colorimetry)	10 min	–	1 nM	Spiked oligonucleotide solutions	[105]
SARS-CoV-2	Oligonucleotide	Optical (LSPR and PPT)	~ 14 min	–	0.22 pM	Spiked oligonucleotide solutions	[24]

SWV, square-wave voltammetry; CA, chronoamperometry; CV, cyclic voltammetry; SPR, surface plasmon resonance; SMR, silicon microring resonator; LSPR, localized surface plasmon resonance; PPT, plasmonic photothermal effect