Verhoeff Ziehl-Neelsen
for Acid Alcohol Fast Bacteria
Materials
- Verhoeff’s Carbol fuchsin
- Harris’ hemalum, or similar
- 1% hydrochloric acid in 70% ethanol
- Ammoniated water (add 2-3 drops strong ammonia to 200 mL tap water)
Tissue Sample
5µ paraffin sections of neutral buffered formalin fixed tissue are suitable. Other fixatives are usually satisfactory.
Protocol
- Bring sections to water via xylene and ethanol.
- Stain with hemalum for 5 minutes.
- Blue in running tap water.
- Immerse in a Coplin jar of carbol fuchsin for 1 hour at 60°C or overnight at room temperature.
- Decolorise with acid ethanol until sections are pale pink.
- Wash well with ammoniated water.
- Rinse with 95% ethanol.
- Rinse twice with absolute ethanol, 1-2 minutes each.
- Clear with xylene and mount with a resinous medium.
Expected Results
- Acid alcohol fast organisms – red
- Background – blue
Notes
- Do not use an open flame with Verhoeff’s carbol fuchsin. The alcohol content is high enough to ignite.
Safety Note
Prior to handling any chemical, consult the Safety Data Sheet (SDS) for proper handling and safety precautions.
References
- Putt, F.A., (1972)
Manual of histopathological staining methods
John Wiley & Sons, New York, NY, USA