MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



GOLGI METHOD (Rapid) 

 For nerve cells 



Solutions required: 



A. Potass, bichromate 3% . . . . 40 ml. 

 Osmic acid 1% . . . . . . 10 ml. 



This solution must be freshly prepared. 



B. Silver nitrate 075%. 



Technique. 



1. Immediately the animal is killed, tissues are cut into slices 

 about 2 mm. thick and fixed in Solution A for one to three days 

 depending upon the size of the pieces. 



2. After removing excess fixative by blotting, the tissues are 

 rinsed in Solution B until no more precipitate is formed. 



3. Transfer to a fresh lot of Solution B and leave for two days 

 or longer. 



4. With a camel-hair brush carefully brush the precipitate from 

 the surface of the tissue ; then wash well in distilled water. 



5. Dehydrate by immersing for one to four hours, depending 

 upon the size of the pieces, in each of the following : two lots of 

 95% alcohol; two lots of absolute alcohol; one lot of ether- 

 alcohol (equal vols, ether and absolute alcohol). 



6. Embed in Celloidin or L.V.N. 



7. Sections 6o-ioo/^ are mounted on slides and covered with 

 Canada balsam in benzol or cristalite, without cover glasses 

 {see L.V.N, technique, page 26). 



Results: 



Background, dull yellow. Nerve cells and their processes, 

 black. Blood vessels, black. 



GRAM'S IODINE 

 For bacteria in sections 



Solutions required: 



A. Carbol gentian violet. 



B. Gram's iodine. 



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