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Cleaning DNA - (Jun/22/2013 )

Hallo ,

I did some phenol-chloroform extractions, however I only did the phenol-chloroform step once and not a few times.
Now I noticed that in most protocols they advise you to do it untill the interphase is clean.

I was wondering: can I redo the pheno-chloroform extraction step again even after I already did an ethanol precipitation on the DNA samples?
Or is there another way to, perhaps, clean the DNA even more?

-lyok-

It is a bit of a question of how clean do you need your DNA to be? If you need it for genome sequencing or something like that, then I would recommend having it as clean as possible, but if you are just doing PCR or similar things (cloning etc.) then you don't need it all that clean.

You can re-do the phenol chloroform extraction on the precipitated DNA. It might be easier to pass it through a commercial column based DNA prep though.

-bob1-

bob1 on Sat Jun 22 21:53:29 2013 said:


It is a bit of a question of how clean do you need your DNA to be? If you need it for genome sequencing or something like that, then I would recommend having it as clean as possible, but if you are just doing PCR or similar things (cloning etc.) then you don't need it all that clean.

You can re-do the phenol chloroform extraction on the precipitated DNA. It might be easier to pass it through a commercial column based DNA prep though.


Yes it is for sequencing.
No PCR.

I see, but the column based DNA preps gave bad results in the past so we changed to phenol-chloroform extraction.

-lyok-