[Histonet] Grocott's stain for fungi

[Kathleen Roberts]

Hi all-

I'm making up the various stock & working solutions for Grocott's stain, 
and I am having a heck of a time getting the 3% methenamine to go into 
solution.  (Not methenamine silver, just plain old 3% methenamine in 
distilled water.)  I know that you have to acid-clean the glassware for 
the methenamine silver & silver nitrate solutions, but do I have to do 
it for 3% methenamine?  I tried heating it, but that did not make a bit 
of difference. AFIP manual  has no other instructions other than "3 g 
methenamine in 100 ml distilled water".

 Is there a shelf life for methenamine?  The bottle we have is pretty 
old, but I am not sure if that would be a factor.

I intend to try acid-cleaning a bottle for the 3% methenamine this 
afternoon, but I wanted to see if anybody had any other suggestions to 
try as well.

Thanks in advance-
Kathleen Roberts
Principal Lab Technician
Neurotoxicology Labs
Dept of Pharmacology & Toxicology
Ernest Mario School of Pharmacy
Rutgers University