Lorraine:

I'll do the short answer first.  We embed without emersing the blocks in paraffin.  This is due to the mess and lack of an easy way to drain the chamber in our embedding center.  I think the other way is probably better for the tissue, but I'm not ready for that battle with my embedding techs.

As for adhession of slides.  We have a slide drier from allegiance which not only has heat, but also uses forced air to fan the heat around.  We use 20 minutes at 60 degrees C for most routine slides.  We dry them in the racks we use on the stainer/coverslipper.

We were having a major problem with immuno's falling off.  We switched to plus slides from aminosiline slides and now air dry our immuno's for at least 2 hours in the racks before putting them in the oven for 40 minutes at 60 degrees C.  We didn't want to do this because of turn around time, but what good is getting the stain done if the tissue fell off.  This has solved most of our problems, poorly processed fat will always be a problem.

Another possiblility is a bad batch of slides.  You should not be able to float a section back off of a good adhesive slide.  Try different adhesive slides like polysilane or aminosilane or another brand of plus (charged) slides.

As for the use of waterbath adhesive with adhesive slides.  The problem with this is with immuno's.  You can get inconsistant staining or artifact from this.  I think the antibody interacts with the protein in the waterbath adhesive which is sitting on top of the adhesive coating on the slides.

Has your workload increased?  Maybe the oven is being opened more often by people putting slides in or it is jammed full and you need to increase your times to compensate.  Or maybe a tech is taking them out too soon.

Are you using an oven on an autostainer?  It may be having problems or the times/temps were changed.

Sorry for the length of message, but I hope one of these ideas helps.  I know how frustrating it can be redoing work.

Ross Stapf
Histology Superviser
Washington Adventist Hospital


>>> "Cornett, Lorraine D"  08/26/02 03:42PM >>>
I would like to know how many people embed out of paraffin at the embedding
center, and how many transfer the blocks to the embedding chamber and embed
without immersing them in paraffin at the embedding center?
All replies and explanations will be appreciated!

Lorraine Cornett
Blue Ridge Pathology Consultants
Kingsport, TN
423 224-6767