The Argentaffi}! Reaction 251 



Disodium phosphate, M/IO: 



disodium phosphate, Na2HP04 anhydrous . 14.2 gm. 

 distilled water 1000.0 ml. 



Working solution: {do not prepare until immediately before use, 

 see step 2 below) 



To 4.5 ml. of ice-cold safranin solution add 0.5 ml. of sodium nitrite 

 solution. The resulting mixture turns deep blue and foams. Keep at 

 to 5°C for 15 minutes for diazotization. Dilute 1 ml. of the solution 

 with 40 ml. of ice-cold disodium phosphate solution and use imme- 

 diately. (pH should he about 7.7) 



procedure: 



1. Deparaffinize and hydrate slides to distilled water. 



2. Place slides in a previously chilled coplin jar and pour over them 

 the freshly prepared diazo-safranin solution: 5 minutes. 



3. Decant stain and wash slides in 3 changes of N/10 aqueous hydro- 

 chloric acid or acid-alcohol (1 ml. cone. HCl/99 ml. 70% alcohol): 

 10-30 seconds total, to remove most of adherent stain. Longer ex- 

 traction lightens the colors but does not improve contrast. 



4. Wash off acid with water (if N/10 HCl is used) or 95% alcohol 

 (if acid-alcohol is used). 



5. Dehydrate, clear, and mount. 



results: 



enterochromaffin granules — black 



gastric gland, chief cell granules — dark red 



Paneth cell granules — red 



mucin — unstained 



nuclei and cytoplasm — pink to red 



Ferric-Ferricyanide Method (Modified Schmorl Technic) 



(LASKY AiND GRECO, 1948; LILLIE AND BURTNER, 1953) 



fixation: 10% formalin buffered with 2% of calcium acetate: 1-3 days. 



solution: 



Ferric-ferricyanide: 



potassium ferricyanide, 1% aqueous 10.0 ml. 



ferric chloride, 1% aqueous 75.0 ml. 



distilled water 15.0 ml. 



procedure: 



1. Deparaffinize and hydrate slides to water. 



2. Stain in freshly prepared ferric-ferricyanide: 5 minutes. 



