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Guanidine + Bisulfit = Problem? - (Apr/11/2007 )

Hi there!

Just a quick question: does anyone know if guanidinehydochloride interfers with the bisulfit-reaction? any good or bad experiences?

(my dna is solublilised in in a guanidinehydochloride containing buffer, and i'm not quite sure if this is ok for the bisulfit.... never done this before, but i can't purify the dna since it's really low concentrated, so it has to work this way - i hope....)



Hi Mike,

oh, never done that... I think it may be worth a try, main problem with Guanethidine should arise when you add acids or bleach, no?
Maybe you test it with a non-precoious sample?

Sorry, no real help...



I haven't had experience with such samples but I would guess that because the guandine has a certain pH, this may stuff up the reaction as the pH needs to be around 5 for the reaction to proceed.

Could you desalt the sample with say a wizard DNA clean up column?



Never tried this before.

But looking at the compounds, I am willing to bet that bisulfite would react with the guanidium ions.

I would suggest a small expriment with some throw away DNA, you might need to increase the concentration of bisulfite to achieve the same degree of deamination.

Best, if you could remove the guanidium ions from your DNA.