STAINING, PRACTICAL AND THEORETICAL 



F. Scarlet R (Herxheimer). 

 Acetone . . . . . . • • 50 ml. 



Alcohol, 70% . . . , . . 50 ml. 



Scarlet R . . . . . . . . i -5 gm. 



Heat on a hot water bath; then allow to cool 

 before filtering. 



Technique: 



1. Fix tissues in Solution A; wash in running water and cut 

 frozen sections. 



2. Mordant the sections in Solution B for three to twenty-four 

 hours; then wash in water. 



3. Immerse in mixture of equal parts of Solutions C and D for 

 twenty to forty-five minutes. 



4. Differentiate in Solution E, examining under the microscope 

 at intervals. 



5. Wash well with distilled water. 



6. Stain with Solution F for about five minutes. 



7. Rinse quickly with 70% alcohol. 



8. Rinse with distilled water. 



9. Mount in neutral glycerine jelly or in Aquamount. 



Results: 



Neutral fats are stained red, whilst fatty acids are deep blue 

 black, haemoglobin, calcium and iron may also be stained. 



Note: Calcium salicylate is added to the formalin fixative to 

 convert soaps, which are sodium and potassium salts of fatty 

 acids, into insoluble calcium soaps. If it is desired to demonstrate 

 how much, if any, soap is present in addition to fatty acids, com- 

 pare stained sections of two pieces of the same material, fixing one 

 piece in Solution A and the other in ordinary 10% formalin. 



References : 



Lillie, R. D. (1948), pp. 161-2. 

 Fischler, F. (1904). 



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