Posted in Staining


MORDANT and ACCENUATOR both are terms used in staining, for substances which enhance staining. However, both have different mechanisms of action. We will be looking at the difference between mordant and accenuator in staining.

Differences between mordant and accenuator


  1. MORDANT serves as a link or bridge between the tissue and the dye, to make the staining reaction possible.
  2. The mordant combines with a dye to form a colored “lake”, which in turn combines with the tissue to form a “tissuemordant-dye-complex”.
  3. Examples of mordants are potassium alum with hematoxylin in Ehrlich’s hematoxylin, and iron in Weigert’s hematoxylin.

More in staining

Click below for a quick summary


  1. ACCENTUATOR, is not essential to the chemical union of the tissue and the dye.
  2. It does not participate in the staining reaction,
    but merely accelerates the reaction.
  3. Examples are potassium hydroxide in Loeffler’s methylene blue and phenol in carbol thionine and carbol fuchsin.
Posted in Histopathology

Some tumors with coffee bean shaped nuclei in pathology

Tumors with coffee bean shaped nuclei
1. Papillary thyroid carcinoma
2. Granulosa cell tumor
3. Brenner tumor
4. Langerhan cell histiocytosis
5. Invasive ductal carcinoma of pancreas
6. Chondroblastoma

Click below for a list of tumors with coffee bean nuclei.