Table 1.

Determination of sensitivity and precision of the SARS-CoV-2 antigen assay

Inactivated Virus Dilution	Calculated input conc. (TCID50/ml)a	Calculated input based on Ortho sample (80 µl)	Ortho Vitros S/C ratiob (reactive cutoff ≥1.0)c			CV%
10−1	4800	384	1150	1180	1160	1.31
10−2	480	38	845	825	826	1.35
10−3	48	4	228	226	229	0.67
10−4	5	0.4	30.2	30.7	31.6	2.30
10−5	0.5	0.04	3.14	3.35	3.3	3.32
10−6	0	0	0.52	0.55	0.51	4.16
10−7	0	0	0.25	0.25	0.26	2.31
10−8	0	0	0.25	0.24	0.23	4.55

a Based on Ortho buffer dilution 4:1.

b Signal/cutoff ratio.

c Each dilution was tested in triplicate.