[Histonet] Re: preparation of chromic acid solution for CAS....

[Gayle Callis]

The chromic acid concentration used with a Grocotts methenamine silver 
stain for fungus will work - 4% to 5% Chromium Trioxide aka chromic acid.

It should work nicely as periodic acid may not completely oxidize some 
fungal walls and you can get a false negative staining result.   Carson and 
Fredenburgh have a very nice publication on this in Journal of 
Histotechnology a few years ago.

This was excellent discussion on CAS versus PAS not too long ago on 
Histonet, so be sure to check Histonet Archives for further information.


Gayle Callis
Research Histopathology Supervisor
Veterinary Molecular Biology
Montana State University - Bozeman
PO Box 173610
Bozeman MT 59717-3610
406 994-6367
406 994-4303 (FAX)