Iodine-Thiosulphate Sequence
To Remove Mercury Pigment
Materials
Solution A
| Material | Amount | |
|---|---|---|
| Iodine | 1 | g |
| Potassium iodide | 2 | g |
| Distilled water | 300 | mL |
Preparation
- Mix the dry iodine and potassium iodide.
- Add 5 millilitres of water and swirl until dissolved.
- Add the rest of the water.
Solution B
| Material | Amount | |
|---|---|---|
| Sodium thiosulphate | 3 | g |
| Distilled water | 100 | mL |
Tissue Sample
Use on sections fixed with a solution containing mercuric chloride.
Protocol
- Bring sections to water by an appropriate method.
- Place into solution A for five minutes.
- Rinse well with water.
- Place into solution B for a few minutes until the tissue is bleached.
- Wash in water.
- Continue with the main stain.
Expected Results
Mercury pigment is removed.
Notes
- The iodine solution given is Gram’s iodine formula. Almost any other iodine solution will be satisfactory. Some technologists prefer to use a 0.1% alcoholic solution (tincture) of iodine.
Safety Note
Prior to handling any chemical, consult the Safety Data Sheet (SDS) for proper handling and safety precautions.
References
- Drury, R.A.B. and Wallington, E.A., (1980)Carleton’s histological technique Ed. 5Oxford University Press, Oxford, UK.
Almost every reference text will include details of the iodine-thiosulphate sequence.
