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Can I clean up Phenol:Chloroform extraction with a column? - (May/10/2010 )

Cleaning up TRIzol extraction with a spin column is certainly possible (See: QIAgen RNeasy Lipid tissues, Invitrogen TRIzol Plus). However, can I take the aqueous fraction from a phenol:chloroform extraction, add ethanol (and possibly salt), and clean the DNA up in a column? Practically no-one has written about this...
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why do you want to do this? If you added alcohol you already precipitated the DNA. Just check the principle of the spin columns, and think what would happen when you load your sample onto it.


Binding of DNA to the column is dependent on the solution the DNA is in. In kits there are usualy binding buffers, it's hart to tell if the aqueous fraction from phenol:chloroform is suitable enough for this.
Anyway DNA precipitated with ethanol would IMHO clog the column.


I was wrong in thinking that in terms of EtOH precipitation-- but all TRIzol-based column kits just asked for adding equal volume of 70% EtOH before loading. I take that to mean EtOH at that concentration is sufficient to allow whatever nucleotides to bind to the filter.