Hi all,
There is an other very good reason to use tap water at some instances. 
After finishing your chromogen step at the end of an IHC staining, 
performed on an acetone-fixed cryostat section you better use tap water 
rather than distilled or MilliQ water. I found out that the nuclear 
morphology is very much destroyed doing so. Just 5 minutes in distilled 
water and your section looks like somebody just walked over it! Even a 
post-fixation step with buffered formaling prior to the distilled water 
rinse is not going to help you.
Who is going to try this and confirm this funny result?

Happy staining!
Chris van der Loos
Dept. of Cardiovascular Pathology
Academical Medical Center
Amsterdam - The Netherlands 

Original Message ----- 
From  Gary Gill  
Date  Wed, 29 Oct 2003 10:26:10 -0500 
To  "'mrl0627@mail.ecu.edu'" , 
histonet@lists.utsouthwestern.edu 
Subject  RE: [Histonet] When to use tap water? 
------------------------------------------------------------------------
The pH of tap water is often higher than that for non-tap water, hence
bluing of hematoxylin occurs slightly more quickly.  Using "designer" 
water
is overkill for staining applications, IMHO and experience.

Gary Gill

-----Original Message-----
From: mrl0627@mail.ecu.edu [mailto:mrl0627@mail.ecu.edu]
Sent: Wednesday, October 29, 2003 10:04 AM
To: histonet@lists.utsouthwestern.edu
Subject: [Histonet] When to use tap water?

Hello, all:
The prof for my graduate course in histology insisted that tap water be 
used
for rinsing slides during certain staining procedures (eg. H&E)although
he did not give a specific reason why.  
When no "flavor" of water is specified in a procedure, I generally
use MilliQ or distilled deionized water.  Is this the safest route to 
take or should one use tap if nothing but "water" is listed?
Thanks for the attention.  Maureen, MS candidate at ECU.

-----Original Message-----
From: "Houston, Ronnie" 
To: "'Morken, Tim - Labvision'" ,
histonet@lists.utsouthwestern.edu
Sent: Tue, 28 Oct 2003 13:05:45 -0500
Subject: RE: [Histonet] Dionized vs distilled water

What quality of water is recommended/regulated for anatomic and clinical
pathology labs?
Ronnie Houston 
Regional Histology Operations Manager 
Bon Secours HealthPartners Laboratories 
5801 Bremo Road 
Richmond, VA 23226 
(804) 287 7972 
ronnie_houston@bshsi.com 
-----Original Message-----
From: Morken, Tim - Labvision [mailto:tpmorken@labvision.com]
Sent: Tuesday, October 28, 2003 12:53 PM
To: 'JCarpenter764@aol.com'; histonet@lists.utsouthwestern.edu
Subject: RE: [Histonet] Dionized vs distilled water

Distilled water is classically produced by heating water to evaporation
and subsequent condensing on a cold surface. In the process most
impurities are either evaporated off ahead of the water (in the case of
most organics), or left behind (in the case of minerals). The water is
also effectively deionized because the salts are left behind. It is
fairly pure water. To get very pure water it needs to be re-distilled
several times.

Deionized water is classically passed through a salt bed or ionized
resin bed that captures the mineral ions (ie, a "water softener").
The water is not necessarily pure, however, especially in regards to 
organic chemicals. Reverse osmosis is also used now days to deionize 
water.
High quality water systems these days are some combination of filters,
distillation, deionizing resins and reverse osmosis. 

Tim Morken

-----Original Message-----
From: JCarpenter764@aol.com [mailto:JCarpenter764@aol.com] 
Sent: Tuesday, October 28, 2003 7:45 AM
To: histonet@lists.utsouthwestern.edu
Subject: [Histonet] (no subject)

while studying for my exam on the different fixatives and there
ingredients....i have noticed that some call for distilled water and
some use the term deionized water.  Is there a difference?


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