MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



Solutions required: 



A. Crystal violet i% in 98% alcohol 20 ml. 

 Ammonium oxalate 1% aqueous 30 ml. 



B. Lugol's iodine. 



C. Malachite green 1% aqueous . . 5 ml. 

 Pyronin, B 1% aqueous . . . . 15 ml. 

 Distilled water . . . . . . 80 ml. 



Technique : 



1 . Stain for thirty seconds with Solution A. 



2. Pour off and wash for thirty seconds with Solution B ; then 

 pour off and blot. 



3. Decolorize for three or four seconds with acetone; then 

 wash with water. 



4. Stain for two minutes with Solution C. 



5. Flood with water, but do not wash; blot dry and examine. 



Results: 



Cells and nuclei, bluish green. Gram-positive organisms, pur- 

 plish black and Neisserieae red. 



MAY-GRUNWALD STAIN 



This stain may be used alone for the cytological examination of 

 blood films, but it is not suitable for parasites. The technique is 

 the same as that for Jenner stain. Its chief use is in conjunction 

 with Giemsa stain {see page 368). 



METHYL GREEN - PYRONIN (UNNA-PAPPENHEIM) 



For gonococci 



Solutions required: 



A. Methyl green . . . . . . i gm. 



Pyronin B . . . . . . . . 0-2 gm. 



Phenol crystals . . . . . . 2 gm. 



Absolute alcohol . . . . . . 10 ml. 



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