We had this same problem with the Brown and Brenn if we let the slides dry
before the differentiation.  No problems if the slides were wet going into
the acetone.  The same thing happens with a ZN for TB.



> Aidan,
>
> I'm having the same problem with my gram stain.  I'm using Brown and
> Hopps. All the bacteria stain blue as if the differention never
> happened.  I've been experimenting with Rosanaline vs pararosaniline to
> see if that makes a difference, but so far nothing has changed.  I tried
> Brown and Brenn, using both versions of Basic Fuchsin, and that didn't
> work, either.
>
> Aidan, what are you using to differientiate with (I'm not familiar with
> the Bancroft & Stevens method)?  I'm using pure Acetone.  I tried the
> old microbiologist's standby of Abs ETOH:Abs acetone, 1:1 and that made
> no difference either.
>
> Sorry, but I'm as baffled as you!
>
> Connie M.
>
> Aidan Schurr wrote:
> >
> > Hi all,
> >
> > We have been having troubles with our gram stain (paraffin) procedure.
The results are not giving sufficient distinction between Gram +ve's
and -ve's.  It has worked in the past, and nothing should have changed.  I
have tried numerous variations, new
> reagents, different differentiation times, and different people doing the
stain, all with no luck.  What is the crucial part of this stain?  Where are
we going wrong?!  I've been using the protocols from Bancroft and Stevens.
> >
> > Many thanks in advance for your help,
> >
> > Aidan, New Zealand.
> >
> > _____________________________________
> > a i d a n   c   s c h u r r
> >  section head, histology
> >   department of pathology
> > hutt valley health
> > high street, lower hutt
> > wellington
> > new zealand
> > telephone ++64 4 5709173
> > facsimile ++64 4 5709214
>
> --
> -oe#017##224##161##177##026##225#
>