MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



4. Pass through absolute 90% and 70% alcohol down to distilled 

 water, as usual. 



5. Stain in the basic fuchsin solution for about five minutes. 



6. Rinse in distilled water. 



7. Stain in the picro indigocarmine solution for ten to twenty 

 minutes. 



8. Rinse in distilled water to which a few drops of hydrochloric 

 acid have been added. 



9. Differentiate in 80% alcohol for half to one minute, until 

 red coloration ceases to come away. 



10. Dehydrate with 70%, 90% and absolute alcohol. 



11. Clear in xylol, and mount. 



Results: 



Chromosomes, brilliant red. Nucleoli and other cell com- 

 ponents, sky blue. 



BREINL'S TRIPLE STAIN 

 For chromosomes 



Solutions required: 



A. Iodine . . . . . . . . i gm. 



Potassium iodide . . . . . . 2 gm. 



Alcohol 90% . . . . . . 100 ml. 



B. Safranin 1% in 50% alcohol 



C. Methylene Blue, polychrome (Unna) 



D. Orange tannin 



Technique: 



1. Fix sections to slides and remove paraffin wax with xylol as 

 usual. 



2. Rinse with two changes of absolute alcohol. 



3. Mordant by immersing in solution A for fifteen minutes. 



4. Rinse well with water. 



5. Stain for at least half an hour in the safranin solution in a 

 closed jar or tube. 



296 



