Multiplex Real-Time Polymerase Chain Reaction for Simultaneous Quantification of Salmonella spp., Escherichia coli, and Staphylococcus aureus in Different Food Matrices: Advantages and Disadvantages
Table 2
Inter- and intra-assay reproducibility of qPCR.
Gene copy numbers
Intra-assay Reproducibility
Interassay Reproducibility
Ct (average)
SD
CV (%)
Ct (average)
SD
CV (%)
Salmonella (ssf)
8.62 × 106
26.86
0.58
2.10
26.36
0.06
0.20
8.62 × 105
30.29
0.53
1.00
29.86
0.20
0.60
8.62 × 104
33.83
0.35
1.00
33.53
0.17
0.50
8.62 × 103
36.47
0.29
0.80
36.22
0.04
0.10
8.62 × 102
39.71
0.13
0.30
39.62
0.02
0.05
8.62 × 101
42.54
0.70
1.00
42.54
0.70
1.00
Escherichia coli (phoA)
7.92 × 105
21.67
0.97
4.00
20.83
0.02
0.10
7.92 × 104
24.99
0.80
3.00
24.29
0.001
0.01
7.92 × 103
29.00
0.89
3.00
28.23
0.03
0.10
7.92 × 102
31.65
1.08
3.00
30.72
0.21
0.70
7.92 × 101
34.39
0.47
1.00
33.97
0.001
0.02
Staphylococcus aureus (nuc)
1.30 × 105
25.67
1.93
6.00
25.08
0.10
0.40
1.30 × 104
28.83
1.44
4.00
28.19
0.04
0.10
1.30 × 103
31.66
0.62
1.00
31.29
0.03
0.10
1.30 × 102
34.70
0.37
1.00
34.79
0.05
0.10
1.30 × 101
37.59
0.16
0.40
40.80
0.14
0.03
Average between three replicates. Average between five different reactions. Ct: cycle threshold; SD: standard deviation; CV: coefficient of variation.
