MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



Technique: 



1. Tissues should be fixed in io% formalin, and frozen sections 

 employed. 



2. Sections are stained for five minutes in the picric acid solu- 

 tion. 



3. Rinse in distilled water. 



4. Stain in the nigrosin solution for one minute. 



5. Wash in distilled water. 



6. Rinse in 95% alcohol. 



7. Clear in Solution C. 



8. Mount in balsam or in Cristalite. 



Results: 

 Eleidin, blue-black. Keratin, bright yellow. 



PROTARGOL - GALLOCYANIN (Foley) 

 For nerve fibres, sheaths and cells 



Solutions: 



A. Protargol . . . . . . . . 1% aqueous. 



(Prepared by sprinkling the protargol powder on 

 the surface of the water and leaving it to dissolve.) 



B. Protargol 1% aqueous . . . • 50 ml. 

 Alcohol 95% . . . . . . 50 ml. 



Pyridine pure . . . . . . 0-5 ml. 



Note: The quantity of pyridine may be varied 

 between o-i ml. and 2 ml. The higher concentrations 

 facilitate the staining of thin fibres, whereas cell 

 bodies and dentrites are better demonstrated with the 

 lower proportions of pyridine. 



C. Boric acid . . .. .. .. 1-4 gm. 



Sodium sulphite anhydrous . . 2 gm. 



Hydroquinone .. .. .. 0-3 gm. 



Acetone . . . . . . • • 15 rnl. 



Distilled water . . . . • . 85 ml. 



Dissolve each reagent in the above order in the 

 water adding the next only after the previous one has 

 been dissolved entirely. 



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