Principle of Prussian blue stain:
Ans. (b) Ferrocyanide to ferroferric cyanide(Ref: Dacie and Lewis Practical Haematology 11th ed, pg 338)Hemosiderin reacts with potassium ferrocyanide to form a blue compound, ferri ferrocyanide; this reaction is the basis of a positive Prussian-blue (Perls') reaction.
Ferrous to ferricyanide
Ferrocyanide to ferroferric cyanide
Ferroferriccyanide to ferrocyanide
Ferrocyanide to ferricferrocyanide
Cellular Pathology