Unna's Orcein-Aniline Blue
for Elastic
Materials
- A red nuclear stain
- Solution A
Material Amount Acetic acid, glacial 1 mL Distilled water 1 L - Solution B
Material Amount Aniline blue 0.5 g Orcein 0.5 g Acetic acid, glacial 2.5 mL Ethanol, 100% 25 mL Distilled water 50 mL Glycerol 10 mL
Preparation
- Dissolve the aniline blue in the water with heat.
- Cool and filter.
- Dissolve the orcein in the ethanol.
- Add the acetic acid and glycerol.
- Combine the solutions.
Tissue Sample
5µ paraffin sections of neutral buffered formalin fixed tissue are suitable. Other fixatives are likely to be satisfactory.
Protocol
- Bring sections to water via xylene and ethanol.
- Stain the nuclei with a red nuclear stain.
- Place into solution A for a few minutes.
- Place into solution B for 1-10 hours.
- Differentiate with solution A until elastic fibres are clear.
- Dehydrate with 95% and absolute ethanols.
- Clear with xylene and mount with a resinous medium.
Expected Results
- Nuclei – red
- Elastic – reddish brown
- Bone – reddish brown
- Background – blue
Notes
- Gatenby & Beams specified water blue rather than aniline blue
- Unna’s method has been more commonly applied in conjunction with other methods, such as Pasini’s trichrome, with solution B (Unna’s solution) being incorporated into other staining solutions.
Safety Note
Prior to handling any chemical, consult the Safety Data Sheet (SDS) for proper handling and safety precautions.
References
- Gray, Peter. (1954)
The Microtomist’s Formulary and Guide.
Originally published by: The Blakiston Co.
Republished by: Robert E. Krieger Publishing Co.
Citing:
Gatenby, J. B. & Cowdry, E. V., (1928)
Bolles Lee’s Microtomist’s Vade Mecum, pp. 280
Blakiston, Philadelphia
