Ziehl-Neelsen stain is used to stain acid-fast mycobacteria. It can also be used to stain few other bacteria like Nocardia. The reagents used are Ziehl-Neelson carbol fucshin, acid alcohol and methylene blue.
Procedure
- Add Ziehl-Neelson carbol fucshin to the slide for five minutes while applying heat.
- This is follwed by a gentle wash with water to cool the slide.
- Acid alcohol is now added to decolorize the slide.
- Wash the slide in water again and counterstain with methylene blue for one to two minutes.
- The acid-fast bacteria retain the red color, and are therefore seen red against a blue background.
