Since we do our immunostaining in a core EM lab, we generally do enhance
the DAB reaction with osmium.  The method I use is to place a small drop
of 1% phosphate-buffered osmium tetroxide on the section after a final rinse
in water, while working in a good fune hood, of course, swirl the slide for
a
second or so to distribute the osmium, and then rinse in water from a squirt
bottle.  The DAB turns dark brown, and there is a very light yellow-brown
counterstain of the secion, which is attractive to my eye.

Hal Hawkins, UTMB Galveston




-----Original Message-----
From: Robbin Newlin Manager, Histology [ mailto:rnewlin@burnham-inst.org
<mailto:rnewlin@burnham-inst.org> ]
Sent: Thursday, January 27, 2000 1:10 PM
To: histonet@pathology.swmed.edu
Subject: dab and osmium


Hi All
        I am looking for a protacol for enhancing DAB with osmium. Does this
exist? I thought I had seen it on the Histonet some time ago.
Thanks in advance
Robbin