Table 3 Ct value and melting temperatures (Tm) of the amplified serial dilution of the one step RT-qPCR and two step RT-qPCR
From: Diagnostic power of one-step and two-step RT-qPCR methods to SARS‑CoV‑2 detection
Standard dilution | Copies/ml | One step RT-qPCR RdRp gene | One-step RT-qPCR N gene | Two step RT-qPCR S gene | Two step RT-qPCR N gene | ||
|---|---|---|---|---|---|---|---|
Ct (Threshold 2) | Ct (Threshold 2) | \(\mathrm{Ct }(\mathrm{Threshold }0.2 )\) | Tm (°C) | \(\mathrm{Ct }(\mathrm{Threshold }0.2 )\) | Tm (°C) | ||
0.1 | 109 | 19.97 | 16.44 | 18.56 | 83 | 19.93 | 85 |
0.01 | 108 | 21.49 | 19.14 | 24.13 | 83 | 25.49 | 85 |
0.001 | 107 | 24.03 | 21.56 | 27.52 | 83 | 28.14 | 85 |
0.0001 | 106 | 27.5 | 23.82 | 32.06 | 83 | 32.31 | 85 |
0.00001 | 105 | 31.56 | 27.31 | 36.05 | 83 | 36.91 | 85 |
0.000001 | 104 | 34.66 | 30.77 | 39.41 | 83 | 39.18 | 85.14 |
0.0000001 | 103 | 36.74 | 33.23 | 41.08 | 83.19 | N.D | – |
0.00000001 | 102 | 40.01 | 37.83 | N.D | – | N.D | – |