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Preserve PCR mix - (Mar/08/2006 )

Is it possible to prepare PCR mix 24h or more before starting PCR?
I mean is it possible to mix H2O+Buffer+MgCl+dNTP+Primer before?
Can we add Taq too?
How many time is it possible to store it and in which conditions (-20°C)?
Thanks for answers


It's definately possible to do so. Many companies sell "master mixes" to which you only have to add primers and template. I've made aliquotes containing primer and the mastermixes, froze them and thawed them when I needed them.

I don't know how many times you can freeze-thaw them, but making single use aliquotes (for instance enough for 10 reactions or so) is a good idea.


Um, I would not add primers until right before use. theoretically, in the cold, this should be fine...but if your polymerase has proofreading activity it might chew them up enough to mess up your reactions, even over time in the freezer. that's the only thing I would change, though, and it may just be paranoia on my part?


I was doing this with regular taq, that has an antibody attached to it so it isn't active before initial denaturation, so it wasn't a problem for me.