Dye

 
 Dye: A coloring substance.

Acid dye

When the staining property is in the acid radical of the neutral salt, the stain is called an acid dye e.g., eosin, picric acid, azo dyes, trypan blue, trypan red, organic G.

Amphoteric

One containing both reactive basic and reactive acidic groups, and staining both acidic and basic elements.

Basic dye

The coloring property of the dye is in the basic radical of the neutral salt, the stain is called a basic dye e.g., hematoxylin, toluidine blue, methylene blue.

Metachromatic dye

A dye that stains tissues two or more colors.

Orthochromatic dye

A dye that stains tissues a single color.

Vital dye

One that penetrates living cells and colors certain structures, without serious injury to the cells.

Basophilic

The structures which stain with the basic dye.

Acidophilic

The tissues or components of a cell that stain with the acid dye.

Eosinophilic

Readily stainable with eosin.

Neutrophilic

Stainable with neutral dyes.

Agyroghilic

Structures stained by silver e.g., reticular fibers.