STAINING, PRACTICAL AND THEORETICAL 



MF4 STAIN 



(Edward Gurr) 



For keratin, etc. 



Technique: 



1. Fix smears, while still wet, in equal parts of ether and abso- 

 lute alcohol for one minute. 



2. Rinse with two changes of 80% alcohol, followed by two 

 changes of 70% alcohol. 



3. Rinse by dipping the slide seven times in rapid succession in 

 ajar of distilled water. 



4. Immerse in the staining solution for two minutes. 



5. Rinse with 70%, followed by 90%, alcohol. 



6. Dehydrate with absolute alcohol. 



7. Clear in xylol and mount. 



Results: 



Cornified cells: orange to red. Non-cornified cells: blue. 

 Reference: Gurr, E. (1956, 1958a). 



MILLON'S REAGENT 



(J. R. Baker's modification) 



For tyrosine 



Solutions required: 



A. Formal saline 



Formaldehyde, 40% - . . . 10 ml. 



Distilled water . . . . • • 83 ml. 



Sodium chloride, 10% aqueous 



Keep a few chips of marble in the stock bottle 

 to maintain neutrality. 



B. Sulphuric acid, 10% . . . . 100 ml. 

 Mercuric sulphate . . . . 10 gm. 



Heat until the mercuric sulphate is dissolved ; then 

 cool and make up the volume to 200 ml. with dis- 

 tilled water. 



The solution is stable. 



C. Sodium nitrite, 0-25% aqueous 



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