Please, help with RNA extraction.

John Watson watson_j at
Fri Jun 21 14:37:41 EST 1996

melia at wrote:
> I have problems when I try to isolate total RNA from mouse liver or brain by
> Chomczynsky method, because the two phases I should obtain after adding
> phenol and chloroform doesn't separate during centrifugation. This
> difficults the extraction and makes the efficiency to be very low.Does
> anybody know why this happens and how to avoid? Is this method good enough
> to extract RNA from those tissues?
> I would appreciate your comments a lot.
> Thank you,

You might include a prespin (12000 x g) subsequent to homogenization and 
prior to addition of chloroform.  I find that this helps during RNA prep 
from vascular smooth muscle and other other tissues with lots of 
connective tissue, so it could help with your liver prep.  For the brain 
prep, a prespin ought to let all that lipid float to the top. 

John Watson
Bristol-Myers Squibb Co.
watson_j at
"If you're not part of the solution, you're part of the precipitate."

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