Isolation of "hot" oligos

[ku at helix.nih.gov]

We use NENSORB columns (from NEN naturally) which are simple to use and pretty 
foolproof. Basically the oligo is added to the column, washed with a TE based buffer, and 
then eluted in 40% ethanol.  The oligo which contains very little free label comes off the 
column in a sharp and reproducible fraction.  We just take the first 20 drops off the column 
(You can also set it up to work as a spin column easier if you are in batch mode). The 
oligos can then be dried in a vacuum centrifuge or used directly in hybridizations.


vilimf01 at mcrcr6.med.nyu.edu wrote:
> 
> Use G25, G50 will eat your 20mers.  I have used G25 for cleaning up my
> labeled oligo's with success on many occasions.
> 
>                                         Usual Disclaimers       SVEN
> 
> In article <kremers-1306961122030001 at ifepmac3.uni-muenster.de>, kremers at uni-muenster.de (Joachim Kremerskothen) writes:
> > Hi netters,
> >
> > we have a problem with the isolation of radioactive-labeled oligos
> > (20mers) after T4 kinase phosphorylation. Ethanol precipitation and gel
> > filtration with Pharmacia`s G50 columns didn´t work very well (maybe
> > because of the lenght of the oligos?). Are there other and better methods
> > for the isolation?


Karen Usdin
National Institutes of Health