MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



B. Distilled water . . . . . . 200 ml. 



Sulphuric or nitric acid, cone. . . 0-5 ml. 



Technique: 



1. Formalin fixed material is embedded in paraffin wax, and 

 sections, 4/x in thickness are fixed to slides with glycerin albumen. 



2. Remove wax with xylol. 



3. Rinse with absolute alcohol. 



4. Pass through 95% alcohol. 



5. Pass through 80% alcohol. 



6. Immerse slides for five to ten seconds in the staining solution 

 at 80-90° C. 



7. Differentiate for one second in solution B. 



8. Dip and agitate slides in a beaker of cold distilled water for 

 one second. 



9. Differentiate further in 80% and 95% alcohol for one to two 

 seconds in each. 



10. Immerse in 80% alcohol for one second. 



1 1 . Dip and agitate the slides in the still warm solution A for 

 one to two seconds. 



12. Return to 80% alcohol for one second. 



13. Repeat steps 11 and 12. 



14. Rinse in distilled water. 



15. Dehydrate by immersing for one second in each of 80%, 

 95% and absolute alcohol. 



16. Immerse in xylol for one minute. 



17. Immerse in a fresh lot of xylol for three minutes. 



18. Mount and examine. 



Results: 



Neurons stand out distinctly against a pale background, and 

 can be followed for a considerable distance. The cytons are stained 

 dark purple emphasizing the blue tint, while the dendrite and axon 

 processes and endings present a somewhat lighter shade, bluish to 

 reddish. Granules in the cell body as well as in the protoplasm 



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