MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



5. Differentiate for one half to one minute with the orange G 

 solution. 



6. Pass through 90%, followed by 70%, alcohol. 



7. Rinse well with water. 



8. Rinse with 70% alcohol, followed by 90%. 



9. Rinse quickly in two changes of absolute alcohol. 



10. Pass through two changes of xylol. 



1 1 . Mount in balsam or in Cristalite. 



Results: 



Parasites are conspicuously stained violet-purple, with deep 

 purple nuclei. Cell walls unstained. 



Note: Alternatively, stages 6, 7 and 8 may be deleted in which 

 case the results will be as follows : parasites not so conspicuously 

 stained violet-purple, with deep purple nuclei. Cellulose walls, 

 yellow to green. Lignified tissue, blue. Tissue nuclei, pale blue 

 with purple nucleoli, and chromosomes deep blue on a purple 

 spindle. 



TITAN YELLOW 

 For the detection of magnesium in plant cells 



Solutions required: 



A. Titan yellow, special for magnes- 



ium test 0*2% aqueous. 



B. Sodium hydroxide 10% aqueous. 



Technique: 



1 . Paraffin sections are mounted on slides and brought down to 

 distilled water in the usual manner, or freehand sections of fresh 

 material may be employed. 



2. Add one or two drops of the Titan yellow solution, followed 

 by one or two drops of the sodium hydroxide solution. 



Results: 



If magnesium is present a red coloration is produced. 



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