MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



CRYSTAL VIOLET 

 A simple stain for spirochaetes 



Solutions required: 



A. Potass, permanganate i% aqueous. 



B. Crystal Violet 2% aqueous. 



Technique: 



1. Air- dried films are fixed by flaming. 



2. Immerse in Solution A for ten minutes ; then wash with dis- 

 tilled water. 



3. Stain for eight to ten minutes in Solution B. 



4. Wash in distilled water ; dry and examine. 



Results: 



Spirochaetes, bluish black and well defined. 



Note: For Treponema pallida^ best results are obtained by 

 warming Solution A on the slide. 



DAHLIA 



For the rapid staining of Heinz bodies in erythrocytes in 

 blood smears of animals poisoned by certain chemicals 

 such as aniline, phenylhydrazine, and its derivatives 



Solutions required: 



A. Dahlia . . . . . . . . 0-2 gm. 



Ethyl alcohol 95% 100 ml. 



Technique: 



1. Moderately thick blood smears are made on scrupulously 

 clean slides, then allowed to dry in air. 



2. Cover the freshly dried smears with the staining solution 

 and allow it to act for thirty seconds. 



3. Pour off excess stain and wash well with running water to 

 remove the excess dye. 



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