Testing inhibition
IPC, within the context of the described triplex assay, was tested against two commonly encountered PCR inhibitors (Figure 3) . The reactions without BSA showed almost complete inhibition at 40 ng/μl humic acid, with only the 100.000 copies IPC amplifying with a 17.5 cycle delay. BSA added to the PCR reaction prevented full inhibition with a minor delay being between 0.5-1 cycle for 40 ng/μl, displaying a clear reduction in inhibition. As expected, BSA had less of an effect on EDTA, which caused inhibition for 2500 and 1250 µM in all PCR reactions. The remaining samples tested in this study were all non-inhibited.