GMS stain


The GMS stain is usually a more difficult stain however lately it has become even harder.  We have made up all fresh reagents, switched to using an autostainer with an old kit and a new kit and changed from 1%periodic acid for 1 hour to using chromic acid.  Some of the fungi stain but not all.  This is also happening with the PAS stain. The collagen in the GMS stains a nice light gray.  

We use the CBG recycler and add acetic acid to our Propar.  Would it be possible for this to affect the stains?  We use reverse osmosis water and to my knowledge the water has always been the same.  When doing the stain I get a silver precipitate if the process goes to long.  Before when this happened the fungi were dark black.  Now they are barely stained.

Any suggestions would be appreciated.


Margaret Perry

Lab Tech

Vet Science Histopath

South Dakota State University


<< Previous Message | Next Message >>