TABLE 2.
Limits of detection of SARS-CoV-2-specific primers and probes using synthetic RNA transcripts in singleplex rRT-PCR assays.
| Lowest numbers of copies/reaction | Orf1ab L LNA-TEX | Orf1ab S LNA-HEX | ||||
|---|---|---|---|---|---|---|
| Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | |
| 1.4 | 34.83 | 34.78 | 34.81 | 35.22 | 35.67 | 35.37 |
| 14 | 30.73 | 30.55 | 30.61 | 32.64 | 32.86 | 32.71 |
| 140 | 27.11 | 27.07 | 27.02 | 29.46 | 29.27 | 29.35 |
| 1.4E+03 | 23.85 | 23.81 | 23.78 | 25.64 | 25.63 | 25.55 |
| 1.4E+04 | 20.04 | 19.96 | 19.91 | 21.97 | 21.91 | 21.88 |
| 1.4E+05 | 16.55 | 16.51 | 16.47 | 18.54 | 18.55 | 18.47 |
| 1.4E+06 | 12.72 | 12.69 | 12.65 | 15.60 | 15.05 | 15.27 |
| 1.4E+07 | 10.03 | 10.00 | 9.92 | 11.22 | 11.19 | 11.11 |
| 1.4E+08 | 7.03 | 6.52 | 6.72 | 7.76 | 8.01 | 7.91 |
| 1.4E+09 | 3.74 | 3.60 | 3.68 | 4.79 | 5.10 | 4.87 |
| NTC | Neg | Neg | Neg | Neg | Neg | Neg |
| Lowest numbers of copies/reaction | Spike 614G LNA-HEX or TEX | Spike D614 LNA-FAM or TEX | ||||
| Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | |
| 1.3 | 34.84 | 34.39 | 34.61 | 36.60 | 36.71 | 36.81 |
| 13 | 32.94 | 31.70 | 31.77 | 33.51 | 34.60 | 33.77 |
| 130 | 29.72 | 29.67 | 29.56 | 30.89 | 30.91 | 30.81 |
| 1.3E+03 | 26.13 | 26.16 | 26.04 | 27.04 | 27.25 | 27.09 |
| 1.3E+04 | 22.61 | 22.64 | 22.55 | 22.52 | 22.56 | 22.47 |
| 1.3E+05 | 18.82 | 18.91 | 18.85 | 18.88 | 18.95 | 18.81 |
| 1.3E+06 | 15.14 | 15.09 | 15.02 | 15.24 | 15.17 | 15.09 |
| 1.3E+07 | 11.48 | 11.53 | 11.41 | 11.47 | 11.46 | 11.34 |
| 1.3E+08 | 7.70 | 7.65 | 7.61 | 7.74 | 7.76 | 7.65 |
| 1.3E+09 | 3.89 | 3.91 | 3.97 | 4.30 | 4.31 | 4.22 |
| NTC | Neg | Neg | Neg | Neg | Neg | Neg |
| Lowest numbers of copies/reaction | Spike N501 LNA-FAM | Spike 501Y LNA-HEX | ||||
| Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | |
| 1.4 | 35.55 | 35.76 | 34.51 | nd | nd | nd |
| 14 | 32.09 | 32.28 | 32.51 | 33.98 | 34.83 | 33.60 |
| 140 | 28.99 | 28.73 | 29.38 | 32.42 | 31.71 | 31.58 |
| 1.4E+03 | 25.64 | 25.55 | 25.97 | 27.88 | 27.94 | 28.22 |
| 1.4E+04 | 22.16 | 22.18 | 22.26 | 24.51 | 24.55 | 24.60 |
| 1.4E+05 | 18.58 | 18.54 | 18.54 | 21.01 | 21.04 | 20.95 |
| 1.4E+06 | 14.85 | 14.78 | 14.95 | 17.47 | 17.56 | 17.55 |
| 1.4E+07 | 11.34 | 10.96 | 10.98 | 13.53 | 13.67 | 13.69 |
| 1.4E+08 | 8.40 | 8.45 | 8.35 | 10.25 | 10.40 | 10.29 |
| 1.4E+09 | 4.02 | 3.92 | 4.60 | 6.23 | 6.79 | 6.41 |
| NTC | Neg | Neg | Neg | Neg | Neg | Neg |
| Lowest numbers of copies/reaction | E Sarbeco-FAM | ||
|---|---|---|---|
| Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | |
| 1.3 | 35.79 | 36.46 | 35.96 |
| 13 | 32.29 | 32.38 | 32.33 |
| 130 | 28.33 | 28.21 | 28.27 |
| 1.3E+03 | 23.79 | 23.82 | 23.61 |
| 1.3E+04 | 18.53 | 18.52 | 18.63 |
| 1.3E+05 | 14.85 | 14.84 | 14.96 |
| 1.3E+06 | 11.39 | 11.38 | 11.44 |
| 1.3E+07 | 7.62 | 7.61 | 7.81 |
| 1.3E+08 | 5.62 | 5.67 | 5.71 |
| 1.3E+09 | 3.01 | 3.09 | 3.13 |
| NTC | Neg | Neg | Neg |
| Lowest numbers of copies/reaction | N LSPQ-HEX | ||
| Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | |
| 1.4 | nd | nd | nd |
| 14 | 36.66 | 36.76 | 36.71 |
| 140 | 32.54 | 32.00 | 32.33 |
| 1.4E+03 | 28.80 | 28.76 | 28.58 |
| 1.4E+04 | 25.30 | 25.36 | 25.26 |
| 1.4E+05 | 21.71 | 21.72 | 21.59 |
| 1.4E+06 | 18.20 | 18.16 | 18.09 |
| 1.4E+07 | 14.65 | 14.64 | 14.51 |
| 1.4E+08 | 11.00 | 11.04 | 11.11 |
| 1.4E+09 | 7.52 | 7.07 | 7.15 |
| NTC | Neg | Neg | Neg |
| Lowest numbers of copies/reaction | B2M-Cy5 or TEX | ||
| Test 1 (Ct) | Test 2 (Ct) | Test 3 (Ct) | |
| 1.3 | 32.90 | 32.84 | 32.97 |
| 13 | 30.73 | 30.88 | 30.96 |
| 130 | 27.98 | 27.49 | 27.64 |
| 1.3E+03 | 24.00 | 23.64 | 23.88 |
| 1.3E+04 | 20.43 | 19.77 | 20.05 |
| 1.3E+05 | 16.20 | 16.21 | 16.38 |
| 1.3E+06 | 12.52 | 12.44 | 12.61 |
| 1.3E+07 | 8.64 | 8.69 | 8.72 |
| 1.3E+08 | 7.10 | 6.90 | 6.95 |
| 1.3E+09 | 3.00 | 3.10 | 3.19 |
| NTC | Neg | Neg | Neg |