[Histonet] Zinc Formalin

[John A. Kiernan]

Zinc-formalin mixtures do not contain mercuric
chloride, so you will not need to do an iodine and
thiosulphate treatment of the sections. 

Ask your supplier to tell you the composition of
his "zinc formalin". Is it an acidic (zinc
sulphate or chloride) or a neutral (zinc
salicylate) formulation? Most zinc formalin
mixtures are acidic, and it may make a difference
if the anion is sulphate or chloride. The
published literature is clouded by trade secrecy,
as are the web sites of those who make the
mixtures. 

The acidic zinc formalin principle is simple:
combine a protein coagulant with a cross-linker.
All the classical late 19th century fixatives did
that, and more. Formalin pigment can be expected
if
tissues are stored for a long time in an acidic
formaldehyde solution.

Hope this helps.

John Kiernan
Anatomy, UWO
London, Canada.
______________________________________
Laurie Colbert wrote:
> 
> Our formalin supplier mistakenly shipped us pre-filled containers containing zinc formalin instead of 10% NBF.  Before I noticed this, three cases had been distributed throughout the hospital (most likely to Surgery).  So, how is this going to affect my tissue?  Is there any post-treatment (such as removing mercury pigment on B-5 fixed tissue) that I need to perform?
> 
> Thanks in advance for any info you can provide.
> 
> Laurie Colbert
> 
> _______________________________________________
> Histonet mailing list
> Histonet <@t> lists.utsouthwestern.edu
> http://lists.utsouthwestern.edu/mailman/listinfo/histonet