MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



Note: At certain developmental and formative stages, some cell 

 walls are stained sharply with the safranin, while other portions 

 will appear faint blue. 



SAFRANIN - ANILINE BLUE 



For plant tissues, particularly for chromosomes and cell 



walls 



Solutions required: 



A. Safranin i% aqueous. 



B. Aniline blue i% in absolute alcohol. 



Technique: 



1 . Paraffin sections are fixed to slides ; de- waxed with xylol, and 

 passed through descending grades of alcohol down to distilled 

 water as usual ; alternatively freehand sections may be employed. 



2. Stain for fifteen minutes in the safranin solution. 



3. Wash in distilled water. 



4. Rinse in 70% alcohol, followed by 90%. 



5. Rinse in absolute alcohol. 



6. Stain for two minutes in the aniline blue solution. 



7. Rinse quickly but thoroughly with two changes of absolute 

 alcohol. 



8. Wash with two changes of xylol. 



9. Mount in balsam. 

 Results: 



Chromosomes, red. Nucleoli, red. Cytoplasm almost colourless. 

 Cellulose walls, blue. 



SAFRANIN - DIANIL BLUE G 

 For the differential staining of Peronosporaceae 



Solutions required: 



A. Phenol crystals . . . . . . 10 gm. 



Lactic acid . . . . . . . . 10 ml. 



Glycerin . . . . . . . . 20 ml. 



Absolute alcohol . . . . . . 20 ml. 



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