SECTION TWO 



3. Rinse in distilled water. 



4. Immerse in solution B (phosphomolybdic acid) for twenty 

 minutes. 



5. Wash in distilled water. 



6. Rinse in tap water. 



7. Immerse in eosin (solution C) for thirty minutes. 



8. Wash in tap water. 



9. Immerse in light green SF (solution D) for ten minutes. 



10. Rinse quickly with tap water. 



11. Dry rapidly but carefully with filter paper. 



12. Dehydrate with two changes of absolute isopropyl alcohol. 



13. Clear in xylol. 



14. Mount in Emexel, D.P.X., Clearmount or Canada balsam 

 in xylol. 



Results: 



The author (Hrsel) found after a number of tests on proteins 

 having different isoelectric points and varying tryptophane con- 

 tents, that the eosin stained tryptophane-containing proteins, 

 while the light green was taken up by amino groups. However, 

 ribonuclease, which is devoid of tryptophane, was stained by 

 the eosin, while pepsin, which is known to contain tryptophane, 

 was not stained by the eosin. Chromium trioxide (chromic acid) 

 reacts with tyrosine, cysteine, cystine and proline and very 

 intensely with tryptophane. Root meristems of plants stained by 

 the author (Hrsel) exhibited a strong reaction in the nucleoli. 



Reference: Hrsel, I. (1957). 



EOSIN AZUR 2 - HAEMATOXYLIN (Maximow) 



For demonstration of inflammatory changes in haemo- 



poietic tissues 



Solutions required: 



A. A2ur 2 eosin .. .. .. o-i gm. 



Distilled water . . . . . . 100 ml. 



Heat to boiling point, then allow to cool. 



B. Solution A (as above) . . . . 10 ml. 

 Distilled water . . . . . . 50 ml. 



C. Ehrlich haematoxylin. 



193 



