Posted in Staining

DIFFERENCE BETWEEN MORDANT AND ACCENUATOR 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

MORDANT

  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

ACCENUATOR

  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 Hematopathology

Periodic acid schiff (PAS) staining patterns in hematopoietic cells

Different hematopoetic cells stain differently with PAS stain. Let’s look at various PAS staining patterns in hematopoietic cells.

Pattern of PAS staining- Hematopoietic cells- CONTENTS
  1. Myeloid precursors and neutrophils
  2. Monocytes and it’s precursors
  3. Erythroid precursors and red blood cells
  4. Megakaryocytes and Platelets
  5. Lymphocytes and lymphoblasts
  6. Eosinophils and Basophils

VIEW THE SLIDE SHOW

1. MYELOID PRECURSORS AND NEUTROPHILS
Myeloid precursors show diffuse PAS positivity
Neutrophils show intense granular positivity

2.MONOCYTES AND THEIR PRECURSORS
Monocytes and their precursors show variable diffuse positivity.

3.ERYTHROID PRECURSORS AND RED BLOOD CELLS (RBCs)
Red blood cells are PAS negative
Erythroblasts show globular /granular PAS positivity
Normoblasts show diffuse PAS positivity

4. MEGAKARYOCYTES AND PLATELETS
Megakaryocytes and platelets are diffuselt PAS positive.

5. LYMPHOCYTES AND LYMPHOBLASTS
Lymphocytes show granular PAS positivity
Lymphoblasts show Block positivity

6.BASOPHILS AND EOSINOPHILS
Both basophils and eosinophils are negative for PAS