Microorganisms are tiny very small sized creatures not visible by our naked eye.
They have refractive index similar to the refractive index of Aqueous medium, so it is unable to see them with naked eyes.
Staining is the procedure used for making microorganisms visible, Stains bind to the outer surface of cell wall.
Sometimes a stain unable to bind to the microorganism so in that case Mordants were used that increase the affinity of stain towards cellular components.
CLASSIFICATION OF STAINS:
Acidic Stain: If the stain after dissociation imparts negative charge and binds to positive cellular component, this is called as Acidic Stain.
EXAMPLE: Eosin Stain.
Basic Stain: If the stain after dissociation imparts positive charge and binds to negative cellular component, this is called as Basic Stain.
EXAMPLE: Methylene Blue.
Neural Stain: If the stain after dissociation imparts both negative and positive charge this is called as Basic Stain.
EXAMPLE: Leishman stain
On the basis of technique, they can be
Simple Staining: In this technique single stain is used.
Differential Staining: In this technique more than one stain is used.
Comments
Post a Comment