AW: [Histonet] decalcifiers and Safranin O staining

[Gudrun Lang]

HCl has a acid-constant of -6 (strong acid) and formic acid has 3,75 (medium
strong acid).
Strong acids saponificate amidgroups resulting in an acid-group,
deamination. Aminogroups are the reactionpartners of the collagen-stains.
Therefore they can't bind to a deaminated collagen. Another function of a
strong acid is to break down the peptidlinkage and generally denaturate a
protein. The three-dimensional configuration of collagen could also
influence the staining affinity.

Doesn't Immunocal consist of formic acid and formaldehyd? I consider, that
the deamination-effect and the break down appear more on underfixed
specimen; and that formic acid isn't strong enough to disturb the
collagen-configuration in the same manner.
My thoughts about it, but no academic evidence.

Gudrun Lang
 
Biomed. Analytikerin
Histolabor
Akh Linz
Krankenhausstr. 9
4020 Linz
+43(0)732/7806-6754
-----Ursprüngliche Nachricht-----
Von: histonet-bounces <@t> lists.utsouthwestern.edu
[mailto:histonet-bounces <@t> lists.utsouthwestern.edu] Im Auftrag von Michele
Wich
Gesendet: Mittwoch, 19. Dezember 2007 19:24
An: histonet <@t> lists.utsouthwestern.edu
Betreff: [Histonet] decalcifiers and Safranin O staining

Can anyone explain the chemistry behind decalcifying agents and the
Safranin O procedure?...Specifically, why does using Immunocal (formic
acid) as a decalcifier yield beautiful Safranin O staining while RDO
(HCL) almost totally eliminates staining? Does HCL do something to the
proteoglycans that formic acid does not?

 

~Michele

 


This communication is intended solely for the use of the addressee and may
contain information that is legally privileged, confidential or exempt from
disclosure.  If you are not the intended recipient, please note that any
dissemination, distribution, or copying of this communication is strictly
prohibited.  Anyone who receives this message in error should notify the
sender immediately and delete it from his or her computer
_______________________________________________
Histonet mailing list
Histonet <@t> lists.utsouthwestern.edu
http://lists.utsouthwestern.edu/mailman/listinfo/histonet