Table 3. Limit of detection of IS6110 RPA and IS1081 RPA.
DNA amount | 0 fg | 0.5 fg | 0.78 fg | 1 fg | 1.56 fg | 3.13 fg | 5 fg | 6.25 fg | 10 fg | 12.5 fg | 20 fg | 25 fg | 30 fg | 40 fg | 50 fg | 100 fg | 500 fg | 1 pg | 5 pg | 10 pg | 50 pg | 100 pg | 0.5 ng | 1 ng |
IS6110 positive/tested | 0/8 | 2/5 | 0/4 | N/A | 0/4 | 1/4 | 2/4 | 4/4 | N/A | 4/4 | N/A | 4/4 | N/A | N/A | 8/8 | N/A | 5/5 | N/A | 4/4 | 3/3 | 4/4 | N/A | 4/4 | N/A |
IS1081 positive/tested | 0/8 | N/A | N/A | 0/3 | N/A | N/A | 0/2 | N/A | 5/8 | N/A | 5/5 | N/A | 5/5 | 5/5 | 5/5 | 3/3 | 3/3 | 3/3 | N/A | 3/3 | N/A | 3/3 | N/A | 3/3 |
Results shown are for purified DNA extracted from M. bovis BCG. DNA concentrations were measured prior to the preparation of serial dilutions for testing by RPA. The numbers of positive test results and the total number of tests run at each concentration of DNA are recorded.