Stripping Blots - MSI warning

[Robert J. Forster]

Dear Probers:

I feel I should make the community aware of a recent problem we have had
with MSI Magnacharge membranes.  After stripping the membranes with 0.4 N
NaOH for 30 mins. (MSI recommends 0.5 M NaOH for 1 hour) we find that the
membranes are well stripped but that YOU CANNOT REPROBE! We had no
problems using this technique in the past and it appears to be related to
a reformulation of the membrane on the part of the manufacturer. 
Stripping with a boiling method (0.1% SDS) or washing in 50% formamide, 6x
SSPE at 65C for 30 mins. strips the oligo probe and allows reprobing.  We
have had no trouble using the NaOH stripping protocol with Hybond membranes.

It took us a while to figure out this problem, checked out our probe
labelling, hyb solutions, crosslinker etc.  and I am rather pissed off
that it was traced down to a change by the manufacturer that was not
passed on to the end users.  Not to mention the loss of valuable samples
and time.  

Cheers, Bob


--
R.J. Forster					Bob Forster
Centre for Food and Animal Research		ac562 at FreeNet.Carleton.ca
Agriculture Canada				tel (613) 759-1725
Ottawa, On K1A 0C6				fax (613) 759-1765