MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



B. Kultschitzky's haematoxylin solution. 



C. Lithium carbonate, saturated, 



aqueous . . . . . . lOO ml. 



Potassium ferricyanide i% 



aqueous . . . . . . lo ml. 



Technique: 



1 . Slices of formalin-fixed tissue not more than 5 mm. thick are 

 immersed in Weigert's rapid fixative from four to seven days. 



2. Wash in running water for four to six hours. 



3. Dehydrate and embed in Celloidin. 



4. Stain sections in Kultschitzky's haematoxylin from twelve to 

 twenty-four hours. 



5. Differentiate for several hours in Solution C controlling 

 under the microscope at intervals of one half to one hour, until 

 the white matter is stained blue-black, and the grey matter is 

 stained yellowish. 



Note: For human spinal cord differentiation takes up to twelve 

 hours. Human cerebral cortex requires about four hours. 



6. Wash well in running water. 



7. Dehydrate and clear by the standard Celloidin method. 



8. Mount in cristalite. 



Results: 



Myelin sheaths are stained black, while ground-substance is 

 yellow. 



HAEMATOXYLIN - GENTIAN VIOLET - IODINE 



For demonstrating Gram-positive bacteria 

 and fibrin in sections 



Solutions required: 



A. Haematoxylin (Delafield). 



B. Aniline gentian violet 



C. Lugol's iodine. 



D. Aniline oil. . .. .. .. 20 ml. 



Xylol . . . . . . . . 10 ml. 



E. Erythrosin 5% in absolute alcohol. 



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