MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



D. Potassium chromate neutral, 5% aqueous 



E. Weigerfs Borax Ferricyanide Mixture 

 Borax 1% aqueous . . . . . . 100 ml. 



Potass, ferricyanide . . . . 1-25 gm. 



Technique: 



1 . Fix very small pieces of tissue in Altmann's fluid from 1 2 to 

 24 hours. 



2. Wash, dehydrate, clear and embed in paraffin wax in the 

 usual way. 



3. Cut sections from 4 to 5jLt in thickness and affix them to 

 slides. 



4. Remove paraffin wax with xylol. 



5. Wash well with absolute alcohol. 



6. Wash with 90% alcohol. 



7. Wash with 70% alcohol. 



8. Wash with distilled water. 



9. Immerse in solution B for 5 minutes. 



10. Wash with several changes of distilled water for a total time 

 of one minute. 



1 1 . Stain with the haematoxylin (solution C) for i minute. 



12. Wash in distilled water. 



13. Immerse in solution D for one minute, which should turn 

 the sections dark blue-black : if they are only light blue in colour, 

 rinse in distilled water and return to the copper acetate solution 

 and if necessary repeat several times until the sections are dark 

 blue-black after a minute in solution D, or until no increase in 

 colour is obtained. 



14. Rinse with distilled water. 



15. Immerse in solution B again for a few seconds; then again 

 rinse in distilled water. 



16. Differentiate under the microscope with a mixture consist- 

 ing of one volume of solution E and two volumes of distilled water. 



17. Wash with tap water for 6-8 hours. 



18. Dehydrate, clear and mount. 



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