Page 20 - PowerPoint Presentation

Procedure

• Sample Preparation: A smear is prepared from a clinical specimen (like
sputum) on a glass slide.

• Heat Fixation: The slide is gently heated to fix the smear.
• Primary Staining: The slide is stained with carbol fuchsin (a red dye) and

heated to facilitate penetration into the bacterial cell wall.
• Decolorization: The slide is rinsed with an acid-alcohol solution which

removes the stain from non-acid-fast bacteria.
• Counterstaining: The slide is then stained with methylene blue or brilliant

green to provide contrast.