AMS 22.1- AMS 24.1 ACCESSORY METAL STAINING SOLUTIONS 621 



22.1 Simard and Campenhout 763, 63:143 



STOCK solutions: I. 6% ammonium thiocyanate; II. 6% sodium thiosulfate; III. 2% 



gold chloride 

 WORKING solution: stock I. 50; stock II. 50; stock III. just enough to produce ppt. 



23 Differentiating Solutions 



23.1 formulas 



23.1 Golgi 1908 test. 1933 Cajal and de Castro Cajal and de Castro 1933, 203 



formula: water 100, sulfuric acid 0.1, potassium permanganate 0.05 



24 Fixing Solutions 



Solutions of sodium thiosulfate are employed to "fix" p]iotoj;rapliic images because 

 both silver chloride and silver bromide are readily dissolved by them, whereas metallic 

 silver is soluble only with difficulty. Wliile it is doubtful how far silver bromide enters 

 into any metal staining reaction, it is inevitable that when tissues are exposed to solu- 

 tions of silver salts a certain amount of silver chloride is formed. As this substance is 

 unstable in the presence of light, it seems reasonable that it should be removed either 

 b}' simple thiosulfate or by one of the solutions given below. Care must be exercised, 

 however, not to remove the silver from fine structures by prolonged exposure to sodium 

 thiosulfate. Most of the formulas given are combined toning and fixing solutions. 



24.1 FORMULAS 



24.1 Bolsi 1927 test. 1933 Cajal and de Castro Cajal and de Castro 1933, 274 



formula: water 95, 40% formaldehyde 5, gum arable 0.05 



24.1 Cajal 1913 21344, 11:255 



formula: water 70, sodium thiosulfate 5, 95% ale. 30, sodium metabisulfite 10 

 note: The original formula calls for "liquid sodium bisulfite." The quantity of dry salt 

 above presumes that Cajal was employing the common technical solution of 38° Be 

 which contains approximately 50% by weight of the dry salt. To restore the original 

 formula 20 Gms. of solution should be substituted. 



24.1 Cajal 1925 see MS 31.1 Cajal 1925b 



24.1 Cajal and de Castro 1933 Cajal and de Castro 1933, 130 



formula: water 100, sodium thiosulfate 25, ammonium thiocyanate 2, potassium alum 

 1, lead acetate 1, gold chloride 0.2 



24.1 Golgi test. 1937 Gatenby and Painter Gatenby and Painter 1937, 513 



STOCK solution: water 100, sodium thiosulfate 15.5, potassium alum 2, ammonium 



thiocyanate 1, sodium chloride 4. Let stand 1 week. Filter. 

 WORKING solution: "used working solution" 40, stock 50, 1% gold chloride 7 



24.1 Raileanu 1930 6630,104:285 



formula: water 62, 95% ale. 38, sodium thiosulfate 1.2 



