Re: Why does ethnol have to be ICE COLD when ading to DNA cells from onions?

Dear Adilesa,

I am not fully sure why ethanol has to be ice cold to extract the DNA from 
onion cells.  It seems that the temperature of ethanol depends on the 
previous temperature of the preparation steps to obtain the DNA.  When 
working with e-coli the incubation stages before adding the ethanol 
required keeping the cells on ice.  Therefore you would want to also add 
cold ethanol so the temperature in the tube remains the same.  Treating 
the cells with ethanol will dissolve any proteins but does not dissolve 
the DNA.  If you tell me more about your experimentation I might be able 
to give you a better answer to your question.

Sincerely,


Michael Watson