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Problems in obtaining tree genomic DNA - (Feb/03/2002 )

When obtaining DNA using CTAB and SDS, I found  large quanitities of white gelatinoid difficult to remove. After the addition of sodium acetate and absolute ethanol the mixture was centrifuged and some white gelatinoid was removed. and then the supernatant  was incubated at -20 .Is this right way?  I do not know the mechanism of sodium acetate in precipitation of DNA.  Do the ether have the effect of remove polysaccharide?
Thank you.


You should definitely centrifuge before addition of NaAc and ethanol. NaAc + ethanol will precipitate the DNA, and even if you haven't put it in -20 C yet I think you will lose some (if not most) of your DNA when you centrifuge and remove the gelatinoid pellet.