Roach & Smith's
Bismuth Hematoxylin for Arginine

Ingredient	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.

 

Tissues
8µ paraffin sections of Bouin fixed tissues are suitable.

 

Method

1. Bring sections to water with xylene and ethanol.
2. Place into bismuth hematoxylin for 10 minutes.
3. Rinse with water.
4. Dehydrate with ethanol, clear with xylene and mount with a resinous medium.

 

Expected results

• Arginine residues  –  black

 

Notes

1. The formula calls for bismuth nitrate pentahydrate, Bi(NO₃)₃.5H₂0.
2. This method demonstrates proteins with an arginine content of about 12% or more.
3. Nuclear histones and myelin basic protein stain strongly.
4. The authors suggest that the bismuth binds to the guanidino groups of arginine.

 

Reference
Roach, J. B., and Allen, A. A., (1997)
Bismuth hematoxylin stain for arginine residues.
Biotechnic & Histochemistry, v.72, Nº 1, p. 49.