Table 3.
The sensitivity and time for single ET-MCDA targeting invA and ipaH genes compared with that of qPCR and conventional PCR techniques.
| Techniquesa | Isothermal amplification | Regions recognized | Multiplex detection | LoD for Salmonella spp. Shigella spp. (no./reaction) | Fastest time (minutes) | LoD time (minutes)b |
|---|---|---|---|---|---|---|
| ET-MCDA | + | 10 | + | 6.25 fg/3.125 fg | 12 | 35 |
| MCDA | + | 10 | − | 6.25 fg/3.125 fg | 12 | 35 |
| qPCR | − | 3 | + | 2.5 pg/2.5 pg | 32 | 56 |
| PCR | − | 2 | + | 25 pg/25 pg | 150 | 150 |
a
ET-MCDA, endonuclease restriction-mediated real-time multiple cross displacement amplification; MCDA, multiple cross displacement amplification; qPCR, quantitative real-time PCR.
b
LoD, limit of detection. The LoD values are the lowest gnomic DNA level that was positively amplified in triplicate. The positive results of qPCR were generated as ct values, which converted to time for detection.