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<DIV>Geoff,</DIV>
<DIV>Thanks for the information on osmium. I have used the stuff for
Scanning EM and know how awful it is to use, so would love to avoid it. I
was going to try staining free floating sections with c-fos, but have decided to
mount the sections onto glass slides first. We have done nickel
enhancement when staining cell cultures, and decided it didn't make much of a
difference. But, maybe your nickel+cobalt recipe would be helpful for our
sections. </DIV>
<DIV>Thanks,</DIV>
<DIV>Gareth</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>Geoff replied to C-fos and osmication question:</DIV>
<DIV>Hi Gareth:<BR><BR> I have not seen an answer to your
question on Histonet so ......... Osmium (1% aqueous or less) will enhance the
DAB reaction product. If your (brain) sections have not been
defatted/delipidized osmium will also stain the lipids (myelin) in the brain.
This may actually reduce the contrast of the DAB-osmium reaction product
depending on where it is. Osmium will also make the sections less flexible so
they should be mounted on slides before exposure. Osmium is expensive and must
be used under a hood ("fume cupboard") as its vapors will fix your corneal and
nasal epithelium. It is also requires some care in its disposal. There are
several less dangerous/expensive ways to enhance the DAB reaction product,
including nickel or nickel+cobalt ions in the DAB-peroxide incubation medium is
popular. While nckel and cobalt are certainly not benign they don't have the
fume problems that osmium does and they are less expensive. I can send you a
nickel+cobalt recipe if you like. In my experience DAB should be 'enhanced' with
something if you want the intensity of the reaction product to be permant. Also,
use DPX as a mounting media.<BR><BR>Geoff<BR><BR></DIV>
<DIV><FONT face=System color=#800080 size=2>Ms. Gareth B. Davis</FONT></DIV>
<DIV><FONT face=System color=#800080 size=2><STRONG>Research Assistant
II</STRONG></FONT></DIV>
<DIV><FONT face=System color=#800080 size=2>Neuro-magnetics Division of
</FONT></DIV>
<DIV><FONT face=System color=#800080 size=2>the Department of
Neurology</FONT></DIV>
<DIV><FONT face=System color=#800080 size=2>Vanderbilt University Medical
Center</FONT></DIV>
<DIV><FONT face=System color=#800080 size=2>615-936-3318</FONT></DIV>
<DIV><FONT face=System color=#800080 size=2></FONT> </DIV>
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