MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



2. Rinse in tap water. 



3. Decolorize for about thirty seconds in 70% alcohol. 



4. Rinse in 70% alcohol. 



5. Blue in Solution B (above). 



6. Rinse well in distilled water. 



7. Immerse in two changes of cellosolve for one minute in each. 



8. Drain and mount in Canada balsam or in Cristalite. I 



Results: 



Nuclei and chloroplasts are stained bluish purple; cytoplasm 

 in a paler shade of purplish blue, or colourless, lignified and cutin- 

 ized tissues are yellow. Unlignified tissues, bluish purple. 



ERYTHROSIN - LACTOPHENOL 

 A general stain for botanical tissues 



Solution required: 

 Erythrosin 1% in lactophenol. 



Technique: 



1. Place sections on slides and add a drop of the staining 

 solution. 



2. Cover with a coverslip and examine under the microscope. 



Results: 



Lignified and cutinized tissues are stained yellow while cellulose 

 walls are unstained. Nuclei and dense protoplasmic contents are 

 red. Cytoplasm of vacuolated cells appear pink, while chloro- 

 plasts, slime plugs in sieve, tubes, etc., are red. 



GRAM'S IODINE 

 A general stain for botanical tissues 



Solutions required: 



A. Gram's iodine. 



B. Glycerine 50% aqueous. 



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