CsCl vs column kits

[Bob Kodrzycki]

cynthia stryker (cstryker at unlinfo.unl.edu) wrote:
: We are still doing CsCl plasmid (&sometimes genomic) preps.  I'd 
: appreciate comments, + or -, on the various column kits available. 
: Thanks in advance.  Cindy at UNL

We switched from doing CsCl DNA preps to using QIAGEN columns for all of 
our plasmid preps.  The QIAGEN preps are easy and seem to give more 
consistantly (high) yields of plasmid than CsCl.  The DNA quality seems 
to be good although sometimes I do phenol extract it after the final step 
in the kit.  

The elimination of Ethidium bromide from the DNA prep is a major plus.  
Also there is no danger of sticking yourself with a needle (laced with 
EtBr).  The QIAGEN system works on gravity flow rather than 
centrifugation and the columns are designed so that they don't dry out if 
you forget about them.  Thus it's possible to do you plasmid 
purifications while you are doing something else without fear of messing up.

Bob K
bkodrzyc at awod.com