Dear Sharon,
putting as much gelatin as Gayle suggests will always give you background.
The original methods from the 40's and 50's used a pinch of gelatin (Food
Grade) well dessicated and 2-3mls of 3% Potassium Dichromate in the
floatation bath already at about 45C, dissoloving the gelatin before adding
the dichromate.
The action was twofold in that the gelatin acted as an adhesive and the
dichromate acted as a weak etchant on the glass. Results were satisfactory
for all routine histology and usually even retics. were ok.
If you have any background at all, you've used too much of a "pinch" of
gelatin, and you must clean out your bath daily or you'll get Bacteria and
fungi growing in it.
But for IPX there's no substitute for silanised slides.
Regards Mike (Downunder)
-----Original Message-----
From: Marshall, Sharon, Mrs <marshall@anat.uct.ac.za>
To: uvsgc@msu.oscs.montana.edu <uvsgc@msu.oscs.montana.edu>
Cc: histonet@pathology.swmed.edu <histonet@pathology.swmed.edu>
Date: Friday, 19 February 1999 11:28
Subject: chrome gelatin


Hi Gayle,

Read in one of your e-mails that you sometimes use chrome gelatin to
coat slides with. I have only ever used polylisine,albumin or apes.
I have mostly been using apes. I would like to know how you make the
chrome gelatin up. I would like to try it. Our apes method works
quite well but is quite a long process. Nobody around here seems to
have heard about plus charged slides. I do not think I will consider
using them though. They sound expensive.

Thanks
Sharon Marshall
Anatomy & Cell Biology
University of Cape Town
South Africa
e-mail: marshall@anat.uct.ac.za