How is the Acid Fast Staining Technique Performed?
The procedure typically involves the following steps:
1. Application of Primary Stain: The specimen is first stained with a primary stain, usually carbol fuchsin, which is a red dye. 2. Heat Fixation: Heat is applied to the slide to facilitate the penetration of the stain into the waxy cell wall of the bacteria. 3. Decolorization: The slide is then treated with an acid-alcohol solution. Acid-fast bacteria retain the primary stain due to their mycolic acid-rich cell walls, whereas non-acid-fast bacteria do not. 4. Counterstaining: A counterstain, such as methylene blue, is applied. Non-acid-fast cells will appear blue, while acid-fast cells remain red.
