MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



. C. Ethylene glycol, pure, anhydrous . . 85 ml. 

 Distilled water . . . . . . 15 ml. 



D. Ehrlich or Delafield haematoxylin. 



Technique: 



1. Fix material in 10% formalin and cut frozen sections. 



2. Wash sections in water for two minutes or longer to remove 

 the formalin. 



3. Dehydrate the sections by agitating gently in pure anhydrous 

 ethylene glycol for three to five minutes. 



4. Immerse the sections in the stain (solution B) for two to 

 three minutes, with gentle agitation. 



5. Differentiate by agitating gently in 85% ethylene glycol 

 (solution C) from one to ten minutes, controlling by examination 

 under the microscope while the preparation is still wet. 



6. Transfer to distilled water for three to five minutes. 



7. Counterstain with Ehrlich or Delafield haematoxylin. 



8. Wash well in tap water. 



9. Mount in glycerine jelly. 



Results: 



Nuclei, blue. Fat, orange to red. Cholesterol, red. Normal 

 myelin, unstained. Fatty acids, unstained. 



SCARLET R 

 For staining fat, etc. in animal tissues 



Solutions required: 



A. Scarlet Red, saturated in equal 



volumes of acetone and 70% 

 alcohol. 



B. Ehrlich or Delafield haematoxylin. 



Technique: 



I. Tissues are fixed in formalin and frozen sections are em- 

 ployed. 



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