It's pretty easy to make up from first principles and is properly referred
to as Sorensen's Phosphate Buffer. Most good Haematology text books have
recipes in their appendices, and you have a choice of molalities etc. It is
common to make up a stock 0.66Mol stock solutions and then dilute this as
high as 1:40.  If you use a preservative it is an extremely stable buffer
(Is used for calibrating pH Meters and Blood Gas Machines).Roughly equal
volumes will give you a pH of 6.8-6.9, which is recommended for May Grunwald
and Jenner Giemsa and Leishman Sequences, while 6.6 is often used for
Wright's and for Rapid Diff formulations including Fields Stains A & B, pH
7.2 is recommended for peripheral blood films both thick and thin for
screening for malarial parasites (Easier to see Chromatin dot).
The only reason a lot of people used to use the Gurr product was that it was
in compressed tablet form, with one tablet making 500mls of buffer, the
tablets were extremely stable and a shelf life of ten or so years could be
expected if you kept it tightly closed.
Regards Mike Rentsch
Australian Biostain (Downunder)
-----Original Message-----
From: Tamara Howard <howard@cshl.org>
To: Histology listserver <histonet@pathology.swmed.edu>; Microscopy
Listserver <Microscopy@sparc5.microscopy.com>
Date: Thursday, 7 December 2000 9:04
Subject: Gurr buffer recipe?


>Would anyone happen to have the actual recipe for Gurr's buffer? I think
>it is some phosphate formulation - we've been hunting the recipe and have
>found some refs, but will have to interlibrary the journals/books and we
>thought we'd give the 'net a try, first.
>
>I know we can buy the pre-made buffer, but we need such a tiny amount that
>we'd rather make it from scratch (plus we want to know what it is!).
>
>Thanks!
>
>Tamara Howard
>Cold Spring Harbor Laboratory, NY
>
>