STAINING, PRACTICAL AND THEORETICAL 



MILLON'S REAGENT 



(R. R. Bensley & I. Gersh's modification) 



For tyrosine 



Reagents required: 



A. Nitric acid (sp. gravity i'42) . . 30-3 ml. 

 Distilled water . . . . .. 20-2 ml. 



Shake thoroughly, in a stoppered bottle, then leave 

 to stand for forty-eight hours. 



B. Reagent A.. 

 Distilled water 

 Mercuric nitrate 



10 ml. 

 90 ml. 

 18 gm. 



Shake at intervals, in a stoppered bottle, over a 

 period of several days ; then filter. 



C. MUlon's reagent {Bensley & Gersh) 



Reagent A. . . . . . • • 0-3 ml. 



Reagent B 

 Sodium nitrite 



D. Reagent A. . 

 Distilled water 



40 ml. 

 0-14 gm. 



10 ml. 

 39 ml. 



Technique: 



1. Place a section of fresh material on a slide. 



2. Cover with a few drops of solution C (Millon's reagent) 

 and leave it to act for about ten to fifteen minutes. 



3. Rinse with reagent D. 



4. Wash with water. 



5. Examine under the microscope. 



Result: 



Tyrosine and tyrosine-containing proteins: orange to brick red. 



Notes: 



{a) Over-exposure to the action of the Millon reagent produces 

 a marked reduction in the colour, and optimum time for a par- 

 ticular tissue has to be determined experimentally. It may be 



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