Dissolving Qiagen purified DNA

[Martin Leach]

In article <3cnede$p83 at mark.ucdavis.edu>, dobates at ucdavis.edu (Dave Bates)
wrote:

> I seem to be having problems getting the DNA pellet from Qiagen to
> dissolve completely in TE. I always seem to end up with some
> precipitate still not in soution even if I heat it up to 65C. The DNA
> seems to be clean (260:280 >1.8) I get a good yield (300-500ug per
> 100ml LB), and it works effectively for transfections, but has this ppt
> in it. I get a reduction in transfection efficiency if it's freeze
> thawed over a long period of time (>3months), but that seems to be the
> only problem. However, I'm using this DNA to perfuse through a
> micropipette and the ppt keeps blocking the pipette. Even when I spin
> it I sometimes get blockages. Any suggestions on how to get it to
> dissolve completely?
> 

I sometimes get a non-dissolvable part of the qiagen prep...i put this down
to resin or something coming off of the column...
if you want it particle free...try a phenol/choloroform extraction of
it...any ppt. should go to the bottom and you can re/ppt the dna 

:)

good luck 

Martin


-- 

.....          Martin Leach                Email:leach at mbcrr.harvard.edu 
   _|____      Dept. of Pharmacology       Phone: (617) 638-5323        
   / o  /      Boston Univ. School of Med. Fax:   (617) 638-4329         
 _/  |-/__==/  80 E. Concord St. (L603)
(BULLDOZER) \_ Boston MA 02118            "Not the old underpants on your
               USA                           head.....WIBBLE" -BLACKADDER 
p.s. try BioMOO (virtual biology on the internet - telnet
bioinfo.weizmann.ac.il 8888)