Table 2.
Detection capacity of multiplex quantitative PCR.
| Oligos for a single target | Oligos for three targets | Δ Ct | Δ copy number (log 10) | ||||
|---|---|---|---|---|---|---|---|
|
DNA standard copy number of target DNA (number of reactions) |
Mean Ct value |
Mean measured copy number (log10) |
DNA standard S. pneumoniae, H. influenzae and N. meningitidis copy number of each target DNA |
Mean Ct value | Mean measured copy number (log10) | ||
| Spn 10000 (5) | 27.7 | 27.8 | 0.1 | ||||
| Spn 2000 (5) | 30.2 | 30.4 | 0.2 | ||||
| Spn 500 (7) | 32.7 | 32.4 | -0.3 | ||||
| Hi 10000 (5) | 23.8 | 23.7 | -0.1 | ||||
| Hi 2000 (5) | 26.4 | 26.4 | 0.0 | ||||
| Hi 500 (7) | 28.6 | 28.5 | -0.1 | ||||
| Mc 10000 (4) | 27.6 | 27.4 | -0.2 | ||||
| Mc 2000 (4) | 30.5 | 30.0 | -0.5 | ||||
| Mc 500 (6) | 32.5 | 32.3 | -0.3 | ||||
| Spn (23 clinical samples) | 27.7 ± 7.6 | 3.9 ± 1.8 | 28.2 ± 7.6 | 3.8 ± 2.0 | 0.5 | -0.1 | |
| Hi (50 clinical samples) | 24.1 ± 10.7 | 3.9 ± 2.8 | 24.7 ± 7.6 | 3.8 ± 3.0 | 0.6 | -0.1 | |
| Mc (8 clinical samples) | 22.0 ± 1.9 | 5.2 ± 0.5 | 22.2 ± 2.0 | 5.2 ± 0.5 | 0.2 | 0 | |
Ct = Cycle of threshold; Spn = S. pneumoniae; Hi = H. influenzae; Mc = N. meningitidis
Comparison of using PCR reaction mix with a single DNA standard and oligos for one target organism versus triplex DNA target standard and oligos for 3 target organisms.