Southerns

[Ulrich Maier]

In article <4a9lfi$6ic at mother.usf.edu>, acannons at com1.med.usf.edu says...
>
>Does anyone have suggestions why our blots are suddenly getting a lot of 
>background?  We use random-prime labeled DNA with no purification of the 
>probe.  The background is speckled-like and is very pronounced around the 
>edge of the blot.
>
>Any ideas?  Thanks

Hey,

what is your blotting solution ? I solved the same problem by changing 
from 10x SSC to 0.4M NaOH. It works even with non-charged nylon membranes. 
I think that precipitated salt on the membrane led to the spotty 
background.

Or try a membrane with a lower binnding capacity, such as nitrocelluloses 
membranes.

Hope I could help you,

U. Maier