[Histonet] Formaldehyde concentration measurement

[Tony Henwood]

The following might be of use:

Test for validity of formalin concentrations


Principle:

The Schiff's reagent (PAS stain) is used to detect aldehydes and In this technique it is used to titrate a solution of formalin The concentration of which is unknown.


Solutions:

1.	1 ml of formalin fixative to be tested.
2.	5 ml of 2.4% aqueous sodium bisulphite - prepare fresh.
3.	Schiffs reagent.


Procedure:

1.	Add 1 ml of formalin to 5 ml of sodium bisulphite.
2.	Mix and allow to react for 15 minutes at room temperature stirring from time to time.
3.	Add 100µl of Schiff reagent.


Results:

If solution turns a deep violet than initial concentration of formalin is in excess of 4% (i.e. 1.6% formaldehyde).


Reference:

Jaspers, B., J. Histotechnol (1987) 10 (4): 263-265.



Regards

Tony Henwood JP, MSc, BAppSc, GradDipSysAnalys, CT(ASC)
Laboratory Manager & Senior Scientist
The Children's Hospital at Westmead,
Locked Bag 4001, Westmead, 2145, AUSTRALIA.
Tel: 612 9845 3306
Fax: 612 9845 3318




-----Original Message-----
From: histonet-bounces <@t> lists.utsouthwestern.edu [mailto:histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of Maray Weirauch
Sent: Friday, 21 October 2005 5:17 AM
To: histonet <@t> lists.utsouthwestern.edu
Subject: [Histonet] Formaldehyde concentration measurement


Hi Histonetters,
Does anyone know of a simple, inexpensive way to measure the formaldehyde concentration in a prepared, buffered formalin fixative? Thanks!  Maray

_______________________________________________
Histonet mailing list
Histonet <@t> lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet

**********************************************************************
This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient, please delete it and notify the sender.

Views expressed in this message and any attachments are those of the individual sender, and are not necessarily the views of The Children's Hospital at Westmead

This note also confirms that this email message has been
virus scanned and although no computer viruses were detected, the Childrens Hospital at Westmead accepts no liability for any consequential damage resulting from email containing computer viruses.
**********************************************************************