Figure 6.

Comparison of commercial enzymes for blood PCR. A 232 bp single-copy target was amplified (50 μl) from the indicated volumes of blood using SureDirect PCR mix (A) or another commercially-available PCR blood kits (B–E). All reactions contained 0.4 μM each Quantos primer and were cycled on a SureCycler 8800 instrument, according to each manufacturer's recommendations. PCRs performed with SureDirect PCR master mix were cycled as follows: 5 min at 90°C, followed by 30 cycles of 30 s at 94°C, 30 s at 60°C, 60 s at 72°C. The other commercial kits employ 3-step cycling and 30 cycles, with hold times ranging between 5 and 60 s (annealing) and 15–60 (extension), respectively.