No. We have tested our master mix by heating at 50°C for 1, 3, or 7 days before use in qPCR experiments. In the assays tested (HPRT and GUSB), high PCR efficiency was observed (range of 95.1–103.6% with R2 >0.991). When compared to controls (frozen and unheated master mix), ΔCq values were <0.5, with a few exceptions that were primarily seen when using a low amount of starting template. The small ΔCq values emphasize the stability and robustness of PrimeTime master mix after extreme thermal stress treatment.
For detailed performance data on ambient temperature shipping, see the white paper, Ambient shipping of PrimeTime Gene Expression Master Mix.