MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



Technique: 



1. Spread o-oi ml. of the milk over a carefully measured square 

 centimetre on a scrupulously clean slide. 



Note: The area can best be measured out by marking it on a 

 piece of white paper and placing the slide over the square. 



2. Allow the film to dry; then fix in pure methyl alcohol for one 

 minute. 



3. Apply the stain and allow it to act for about thirty seconds. 



4. Wash with water. 



5. Dry and examine, using a micrometre eyepiece and an oil 

 immersion lens. 



Results: 



Bacteria, deep blue. Background, pale blue. 



NILE BLUE SULPHATE 



For protozoa and yeasts 



Solution required: 

 Nile blue sulphate o-i% aqueous. 



Technique: 



1. Stain from five to ten minutes according to the material 

 and depth of staining desired. 



2. Rinse in distilled water; dry, and examine. 



Note: This stain may also be employed for living amphibian 

 eggs and for Hydra. 



PAPANICOLAOU STAIN 

 For improved dififerentiation of the cells of vaginal smears 



Staining solutions: 



A. Ehrlich or Harris haematoxylin. 



B. Orange G . . . . . . 0-2 gm. 



Alcohol 95% .. .. .. 100 ml. 



Phosphotungstic acid . . . . 0-0x5 gm. 



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