STAINING, PRACTICAL AND THEORETICAL 



PHOSPHOTUNGSTIC HAEMATOXYLIN 



An artificially ripened haematoxylin stain for formalin- 

 fixed material 



(After Ethel Lieb, 1948) 



Place the distilled water in a i litre flask, add the haematoxylin 

 and shake until dissolved. Add the phosphotungstic acid solution, 

 then shake well. Heat to boiling point. Remove the flask from 

 the source of heat; then cautiously add the mercuric oxide and 

 shake to dissolve. Leave the mixture to cool to room temperature 

 or thereabouts. Add the hydrogen peroxide and shake well. 

 Plug the flask lightly with cotton wool, then allow it to stand for 

 a few days to a week. Filter into the stock bottle, when the 

 solution has assumed a deep brownish colour, which indicates 

 that it is ready for use. 



Technique: 



1. Take paraffin section of formalin-fixed material down to 

 water as usual. 



2. Immerse in solution A (potassium permanganate) for five 

 minutes. 



3. Rinse in tap water. 



4. Bleach by immersion in solution B (oxalic acid) for five 

 minutes. 



5. Wash in tap water. 



6. Wash in distilled water. 



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