staining technique microscopy

1. Staining Technique for
Microscopy
Prepared by: Fayiq Ahmad Tantray
Roll no:2209023 (DSC3)

2. What is Staining?
 Stains- chemical substances used to stain
cells are organic compound containing a
benzene ring, a chromophore and an
auxochrome group.
 Stains are used to
• Define and examine bulk tissues for
highlighting (for example- sieve tubes of
phloem, xylem vessels)
•Cell populations (classifying different
bacterial cells, for instance)
•Organelles within individual cells.
 Staining – auxiliary technique; increases

3. Types of Stains
1. Acidic- Anionic
 Used to stain basic component of cell like
cytoplasmic component. Eg. Picric acid,
acid fuchsin, Indian ink, eosin etc.
2. Basic – Cationic
 Used to stain acidic component of cell like
nucleic acid. Eg. Methylene blue, crystal
violet, safranin etc.
3. Neutral – Having no charge
 Made by mixing aqueous solution of
certain acidic and basic dyes. Eg. Geimsa’s
stain, Leishman’s stain, Wright’s stain,

4. Staining techniques
 POSITIVE/DIRECT STAINING: - where the actual cells are
themselves colored and appear in a clear background.
(a) Simple staining: A stain which provides color contrast but gives
same color to all bacteria and cells. Ex: Loeffler’s methylene
blue, Polychrome methylene blue, Diluted carbol fuchsin.
(b) Differential Staining: A stain which imparts different colors to
different bacteria is called differential stain(which contains
more than one stain). Ex: Gram’s stain , Acid fast staining,
Special stains.
 Group
 Gram Stain
 Acid Fast Stain
 Special Structures
 Capsule Stain
 Endospore Stain
 Flagellar Stain

5. Staining techniques
 NEGATIVE/INDIRECT STAINING: where
the cells remain clear (uncolored) and the
background is colored to create a contrast
to aid in the better visualization of the
image.
(a) Indian ink
(b) Nigrosin .

6. Staining Methods

7. SIMPLE STAINING
•Loeffler Methylene blue:
It is generally the most useful of stains for simple staining as it shows
characteristics morphology of polymorphs lycomorphs lymphocystes and
other cells more clearly than stronger stains like gram stains
•Polychrome Methylene blue:
This stain in contrast to blue staining stains acidic cell structures red
purple due to presence of Violet components
•Dilute Carbol Fuchsin:
A very intense stain must be used precautiously as it may stain the whole
cytoplasm in addition to nucleus and bacteria

8. Staining Methods

9. Staining Methods

10. Staining Methods

12. Stain for capsules

13. Stain for capsules

14. Stain for Endospore

15. Stain for flagella

16. THANK YOU