MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



B. Hydrochloride acid, pure . . 0-5 ml. 

 Sodium chloride . . . . 0-5 gm. 

 Methyl alcohol, pure . . . . 75 ml. 

 Distilled water . . . . • • 25 ml. 



C. Potassium permanganate o*i% 



aqueous. 



Technique: 



1 . Smears of sputum or centrifuged urine deposits are fixed by 

 heat in the usual manner. 



2. Immerse the smears in the auramine solution for eight to ten 

 minutes, afterwards washing them with tap water. 



3. Decolorize by immersing for two minutes in each of two 

 changes of Solution B; then wash in tap water. 



4. Immerse in the potassium permanganate solution for about 

 thirty seconds ; then wash with tap water ; blot and dry. 



Note: 



It is claimed that this method gives more positives than the 

 Ziehl-Neelsen technique and there is a saving in time. Using 

 Lempert's method, tubercle bacilli are visible under the two-thirds 

 or the quarter-inch objective with a X 8 eyepiece, and the one- 

 sixth-inch objective may be used for confirmation. 



10. Staining Virus with Primulin 



Solution required: 

 Primulin o-i% aqueous. 



Technique: 



1. Stain for thirty seconds. 



2. Mount if desired in a medium consisting of 100 gm. of best 

 pale gum acacia dissolved in 100 ml. water and 50 ml. glycerine with 

 the addition of 10 gm. chloral hydrate. 



Note: With primulin, which may also be used as a general 

 fluorochrome, a blue-violet fluorescence is obtained. 



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