Mordant

Mordant

 * Chemical which are required to bring about the staining reaction are called mordants.

* They helps to fix the color to the cell components. 

* Basic mordant reacts with acidic stains and acidic mordant reacts with basic stains.

* Examples : Phenol in carbol - fuchsin (Ziehl - Neelsen technique) and iodine in the Gram stainin.