We regularly cut 30-40 µm rat brain sections, place on subbed slides
(0.8% gelatin with 0.05% chromium potassium sulphate) and air dry
overnight before staining. Normally this is absolutely fine,and the
age of subbed slides has varied from a few weeks to very old.

Recently however, we have been having trouble with the same problems
you are experiencing, BUT only on one series and one type of
staining, rather than just any liquid. ie sections have been cut and
placed on slides in series of two, one stays on through the stain
over 4 days but the Cresyl Violet (10 mins) stained sections are
lifting. I don't think it is the age of the subbing therefore, but
possibly is due to the quality of subbing or staining solutions.
There was some discussion on this list a while ago about alkaline
solutions causing gelatin to become more soluble in water, hence the
addition of chrome alum etc etc, and I suspect this is the root of
the problem. Maybe one batch of subbing solution was not made
correctly, or the a batch of staining solution is slightly more
alkaline than usual.

Hope this gives you a starting point.

Cathy


At 2:37 PM -0400 10/4/02, Knight, Brandon wrote:
>I've been having a problem with 40um mouse brain sections coming off of
>subbed slides when placed in any liquid (for instance, when going through
>the staining process).  The edges may fold over, they may wrinkle, or slide
>off completely.  They were sufficiently dried (some for a couple of weeks).
>The slides that I'm using were subbed in August of 2000.  Is it possible
>that the gelatin has degraded and that these slides are no longer subbed, or
>could there be another explanation?
>
>Brandon Knight
>Children's Research Institute
>Center for Genetic Medicine
>Children's National Medical Center
>Washington, D.C.

--
---------------------------------------------------
Cathy Gorrie
Scientific Officer
Neural Injury Research Unit,
School of Medical Sciences,
University of New South Wales
Sydney, N.S.W. 2052

Phone: 61-2-9385 2462
Fax   : 61-2-9313 6252
e-mail: c.gorrie@unsw.edu.au