Table 7.
Limit of detection (LOD) of the qPCR of HRM assay 2
| MTBC member | Genome equivalents | Ct | SD |
|---|---|---|---|
| M. tuberculosis H37Rv | 1,000,000 | 13.37 | 0.01 |
| 100,000 | 16.49 | 0.28 | |
| 10,000 | 19.99 | 0.08 | |
| 1,000 | 23.96 | 0.17 | |
| 100 | 27.46 | 0.22 | |
| 10 | 30.92 | 0.40 | |
| 1 | 33.06 | 1.15 | |
| M. bovis BCG pasteur ATCC 35734 | 1,000,000 | 12.62 | 0.02 |
| 100,000 | 16.02 | 0.03 | |
| 10,000 | 19.69 | 0.24 | |
| 1,000 | 23.82 | 0.19 | |
| 100 | 26.83 | 0.24 | |
| 10 | 30.11 | 0.43 | |
| 1 | 32.6 | 0.61 | |
| M. microti ATCC 19422 | 1,000,000 | 13.68 | 0.05 |
| 100,000 | 17.20 | 0.13 | |
| 10,000 | 20.80 | 0.33 | |
| 1,000 | 24.34 | 0.25 | |
| 100 | 27.77 | 0.04 | |
| 10 | 31.01 | 0.49 | |
| 1 | 33.19 | 0.52 | |
| M. caprae ZH 22914 | 1,000,000 | 17.96 | 0.01 |
| 100,000 | 21.31 | 0.07 | |
| 10,000 | 25.02 | 0.06 | |
| 1,000 | 28.28 | 0.07 | |
| 100 | 31.79 | 0.29 | |
| 10 | 32.42 | 0.38 | |
| 1 | 34.09 | 0.98 |
Determination of Ct values and its standard deviation (SD) of 3 replicates for a dilution series ranging from 1 to 1,000,000 genome equivalents using reference strains M. tuberculosis H37Rv, M. bovis Pasteur ATCC 35734, M. microti ATCC 19422, and the clinical specimen M. caprae ZH 22914. Bold represents the determined LOD for the lowest dilution of which the acceptance criteria (standard deviation < 0.5 and Ct value < 38) were fulfilled.