On Tue, 12 Sep 2000, Heike Grabsch wrote:

> I am a learning-by-doing-histotechnologist (I am a resident (medical
> doctor) in pathology and now have to do my research work by myself,
> because my technician is pregnant)and I need some advice:

It is good news that pathologists in Germany do some of their
own staining!  Pathologists everywhere would benefit greatly from
such experience.

> what can I use instead of hot running tap water for blueing the tissue
> sections after Mayer's hematoxylin?

  Cold tap water is just as good as hot. The requirement for blueing
  is a pH of 7 or a little higher, and it can take as long as 2 or 3
  minutes. Higher pH ---> faster blueing.

> Today I tried 0.5% lithium carbonate for 30 sec. The colour is very nice,
> however I have got a lot of "arbored" precipitates (like small trees, if
> you understand what I mean) on top of the tissue, I washed and washed
> with buffer, with dist. water, with dist. water and Triton X, but I could
> not get rid of this precipitates. What is the problem with lithium
> carbonate as a blueing solution?

  Lithium carbonate is excellent. so is calcium hydroxide (which is
  much less expensive). The crystalline precipitate was probably
  due to moving the slides directly from the Li2CO3 solution into
  alcohol. Most simple inorganic salts of the alkali metals are
  insoluble in alcohol. A rinse in water after blueing should
  solve this problem.


 John A. Kiernan,
 Department of Anatomy & Cell Biology,
 The University of Western Ontario,
 LONDON,  Canada  N6A 5C1