Picro-Ponceaii Staining 165 



Picro-Ponceau Staining 



Picro-Ponceau with Hematoxylin (gurr, 1956) 

 (Van Gieson Substitute, nonfading) 



fixation: any general fixative. 



solutions: 



Hematoxylins, see page 124. 

 Picro-ponceau: 



ponceau S, C.I. 27195, 1% aqueous 10.0 ml. 



picric acid, saturated aqueous 86.0 ml. 



acetic acid, 1% aqueous 4.0 ml. 



procedure: 



1. Deparaffinize and hydrate slides down to Avater, remove HgCl2. 



2. Optional (see Comments): mordant with iron alum before Dela- 

 field's (or similar) hematoxylin. Follow by washing in running 

 water. 



3. Overstain in hematoxylin: 5-15 minutes. 



4. Wash thoroughly in rimning water until slides are deep blue: 10 

 minutes or longer. 



5. Stain in picro-ponceau: 3-5 mintites. (This may be too long for 

 some tissues; the stain acts, in addition to staining, as a destaining 

 agent on the hematoxylin.) Rinse for a few seconds in distilled 

 water and check under microscope. Contintie to stain and destain 

 or differentiate in water imtil nuclei are sharp. 



6. Dip several times in 70% alcohol. 



7. Dehydrate in 95% alcohol, 2 changes, to insure complete removal 

 of excess picric acid. Only that ^vhich has acted as a dye must be 

 left in the tissue. 



8. Dehydrate, absolute alcohol; clear and mount. 



results: 



nuclei — brown to brownish or bluish black 



collagenous and reticular fibers — red 



elastic fibers, mtiscle fibers, erythrocytes, epithelia — yellow 



comments: 



Weigert's type of hematoxylin is excellent for this method, but it is 

 not necessary to precede it with iron mordanting. The iron mordant 

 is present in the staining soliuion. 



