Blot Blocking Agent
Peter M. Muriana
muriana at aclcb.purdue.edu
Mon Jul 19 20:42:58 EST 1993
In article <1993Jul18.202300.2633 at gnv.ifas.ufl.edu>, mschweder at gnv.ifas.ufl.edu (Mark Schweder) writes:
>Folks in this lab for years used Salmon Sperm DNA (SIGMA PN# D1626) as a
Sorry to bust your new find, but Sigma #D1626 is DNA from "Salmon
testes", not from Salmon sperm. Everyone I know has used your new
found blocking DNA (i.e., from Salmon/Herring sperm) for years.
>blocking agent for Southern and Northern blots. The stuff costs about $200
>for 10g. In addition it was quite difficult to prepare.
>One day while looking through the SIGMA catalog, I ran across something
>called DNA Degraded Free Acid From Herring Sperm (PN# D3159) which costs
>about $10 for 10g. It sounded like what we had been spending lots of money
>and time preparing. I ordered some and it easily dissolved in a basic
>solution and works wonderfully as a blocking agent for Southern and Northern
>blots. It costs 1/20 the Salmon Sperm DNA and is easily prepared. If you
>have $10 to burn give it a try.
> Mark Schweder
> Plant Science Laboratory
You may now even save your $10 - there are a number of
hybridization procedures which don't even use sperm DNA as
a blocking agent - just uses casein and SDS. We've been using
such a protocol for 2 years (i.e., Tropix chemiluminescent
detection protocol and others).
More information about the Methods