Table Of Contents
Various type of Staining techniques in Microbiology
| S. NO. | Staining technique | Dye | Application |
|---|---|---|---|
| 1. | Simple Staining | Methylene blue/ basic Fuchsin | Impart same colors to all bacteria |
| 2. | Negative Staining | India Ink/ Nigrosin | Demonstration of bacterail capsules |
| 3. | Impregnation method | Siver | Demonstration of bacterial flagella & Spirochaetes |
| 4. | Differential Staining | ||
| a. Gram staining | primary stain: crystal violet; Gram’s iodine (mordant); decolorizing agent (ethanol/ acetone); Secondary counterstain:safranin | To find out gram-positive bacteria (resist decolorization & retain the color of primary stain i.ee violet)& gram-negative bacteria (decolorized by acetone/ethanol & therefore take counterstain i.e. safranin & appear Red) | |
| b. Acid fast staining | Carbol fuchsin; 20 % Sulphuric acid (decolorization); Counterstain-methylene blue | Staining of Mycobacteria (tubercle & lepra bacilli); acid fastness is due to high lipid content Mycolic acid | |
| c. Alberts stains | Albert II iodine solution | Staining of Corynebacteria diphtheriae |