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sodium acetate for DNA precipitation - (May/02/2007 )

Hello all,

I have been using 3M NaAcetate solution pH5.5 routinly for precipitation of DNA and RNA.

Now, when phenol is used for extraction of nucleic acids : it should be acidic for RNA and Basic for DNA, because if not the DNA will degrade.
So, how come we use an acidic solution (NaAcetate) for DNA precipitation?
when precipitating we dilute this salt by 10 that is 0.3M, but I belicve its buffering capasity keeps the solution at pH5.5.

I thank you all in advance for solving this paradox.

Yael blush.gif


Hmm, I don't think it's the acidity that precipitates the DNA, rather the extremely high salt content allows the DNA to precipitate in alcohol. Does that sound right?