Roach & Smith's Bismuth Hematoxylin
This method demonstrates arginine.
Materials
| Material | Amount | Function |
|---|---|---|
| Hematoxylin | 50 mg | Dye |
| Ethanol, abs. | 5 mL | Solvent |
| Sodium iodate | 10 mg | Oxidant |
| Bismuth nitrate | 50 mg | Mordant |
| Citric acid, 0.5M aqu. | 85 mL | Acidifier |
| Glycerol | 20 mL | Solvent |
| Sodium hydroxide, 1 M aqu. | 19 mL | Alkaliser |
Compounding procedure
- Dissolve the bismuth nitrate into the citric acid solution.
- Add 10 mL of the glycerol, then the sodium hydroxide solution.
- Adjust the pH to 5.2.
- Dissolve the hematoxylin into the ethanol.
- Combine the two solutions.
- Add the sodium iodate dissolved in 1 mL distilled water.
- Stir for 20 minutes.
- Add the remaining 10 mL of glycerol.
This solution has a usable life of about 3 hours.
Protocol
- Bring sections to water with xylene and ethanol.
- Place into bismuth hematoxylin for 10 minutes.
- Rinse with water.
- Dehydrate with ethanol, clear with xylene and mount with a resinous medium.
Expected Results
- Arginine residues – black
Notes
- The formula calls for bismuth nitrate pentahydrate, Bi(NO3)3.5H20.
- This method demonstrates proteins with an arginine content of about 12% or more.
- Nuclear histones and myelin basic protein stain strongly.
- The authors suggest that the bismuth binds to the guanidine groups of arginine.
Safety Note
Prior to handling any chemical, consult the Safety Data Sheet (SDS) for proper handling and safety precautions.
References
- Roach, J. B., and Allen, A. A., (1997)
Bismuth hematoxylin stain for arginine residues.
Biotechnic & Histochemistry, v.72, Nº 1, p. 49.
