RUTHENIUM RED 



220 



SANDISON'S TECHNIQUE 



Ruthenium Red is ammoniated ruthenium 

 oxychloride, a mineral pigment. Conn 

 (p. 187) says that it is used microscopi- 

 cally as a test for Pectin for which some 

 consider it to be specific. 



Ruthenium Tetroxide, as a fixative said to 

 be superior in some ways to osmium 

 tetroxide; but it decomposes readily 

 and penetrates poorly. To prevent 

 decomposition make 1% sol. in sat. 

 chlorine water (Carpenter, D. C. and 

 Nebel, B. R., Science, 1931, 74, lM-155). 



Saffron, a yellow dye obtained from the 

 plant. Crocus sativus. Long cultivated 

 in Persia this plant was introduced into 

 China by the Mongols and throughout 

 the Orient. In the early days of Greece 

 saffron was the official color. Saffron 

 was spread on the streets of Rome to 

 welcome the Emperor and his army. 

 Some monks discovered that by use of 

 an iron mordant and saffron manu- 

 scripts could be cheaply made to appear 

 golden. The City of Florence for a 

 time incorporated the saffron blossom 

 in its coat of arms. Later the City of 

 Basle, Switzerland, followed suit and 

 the "Saffron war" resulted in 1374 A.D. 

 This acknowledged imperial color has 

 come down through the ages; witness 

 the yellow roofs of the Imperial and 

 Forbidden Cities in Peking. For a 

 valuable account read Leggett, W. F., 

 Ancient and Medieval Dyes. Brook- 

 lyn: Chemical Publishing Co., Inc., 

 1944, 95 pp. See also saffron as em- 

 ployed by Vieussens and Leeuwenhoek 

 (Lewis, F. T., Anat. Rec, 1942, 83, 229). 



Saffrosin, see Eosin B or bluish. 



Safranin. In the safranins one nitrogen 

 of the azin group is pentavalent and to 

 this a benzene ring is attached. All 

 are strongly basic. Amethyst violet, 

 azocarmine G, Magdala red, pheno- 

 safranin and safranin O are mentioned. 



Safranin Acid Violet, see Neutral Safranin. 



Safranin B Extra, see Phenosafranin. 



Safranin O (CI, 841) — cotton red, Gos- 

 sypimine, safranin Y or A — Commission 

 Certified. A basic azin dye of great 

 usefulness which is sold as a mixture 

 of di-methyl and tri-methyl pheno- 

 safranins. Conn (p. 97) explains that 

 the shade depends upon their relative 

 proportion. The red is deeper when 

 there is more of the latter. Safranin O 

 can be employed irrespective of whether 

 safranin wasserloslich, or safranin 

 spiritloslich or safranin gelb is called 

 for. The safranin pur, likewise of 

 Grubler and Co., is in his opinion 

 methylene violet (CI, 842). Safranin 

 O is one of the finest nuclear stains 

 especially in the Safranin Light Green 

 method. It is also useful in making 

 certain neutral stains (Neutral Safra- 

 nin). Standardized technique for 



safranin O employing buffered solutions 

 is given by Sawyer, C. H., Stain Techn., 

 1940, 15, 3-7. 



Safranin Y or A, see Safranin O. 



Safranin-Gentian Violet-Orange G. This 

 is Flemming's tricolor stain for nuclei. 

 As described by the Bensleys (p. 88). 

 Fix in Flemming's fiuid and bring 

 paraffin sections down to 95% alcohol. 

 Stain in equal parts sat. safranin in 

 95% alcohol and filtered sat. anilin oil 

 in aq. dest., 2-24 hrs. Rinse in aq. 

 dest. and stain in sat. aq. gentian violet 

 (crystal violet), ^2 hrs. Drop on sat. 

 aq. orange G, 30-60 sec. Drop 95% 

 alcohol on slide until clouds of color 

 cease coming off. Drop on clove oil 

 and differentiate under microscope. 

 Clear in benzol and mount in balsam. 

 Violet should color diffused chromatin 

 strand ; safranin denser part ; and orange 

 G, the background. 



Safranin-Light Green. (Revised by C. H. 

 Sawyer, May 14, 1946.) Stain sections 

 24 hrs. in 2% aq. safranin O and wash 

 out the excess safranin in 0.25% aq. 

 light green (acid violet). Chromatin 

 appears red and acidophilic nuclear in- 

 clusions caused by viruses green. A 

 very brilliant stain but the green fades 

 in the course of a month or two. Stand- 

 ardized safranin O technique advised 

 by C. H. Sawyer (Stain Techn., 1940, 

 15, 3-7) is: overstain deparaffinized sec- 

 tions in 0.1% light green S.F. or fast 

 green FCF in 50% alcohol adjusted to 

 pH 2.4 with 0.1 A^ HCl (100 cc. = 20 cc. 

 0.5% stain + 50 cc. 100% alcohol + 

 8 cc. 0.1 N HCl + 22 cc. aq. dest.) 

 for 4 hrs. or more. Destain in Soren- 

 sen's buffer pH 8, 30 minutes or more. 

 Overstain in 0.1% aq. safranin O at 

 least 4 hrs. Rinse in aq. dest. De- 

 stain in 0.01 A^ HCl (pH 2) or in 0.001 

 N HCl (pH 3) for light green and fast 

 green respectively, 15 min. After rins- 

 ing in aq. dest. dehydrate in 2 changes 

 dioxan, pass through xylol and mount 

 in balsam. As fixatives Sawyer finds 

 Petrunkevitch's paranitrophenol-cu- 

 pric-nitrate-nitric and picro-formol-ace- 

 tic better than Bouin's fluid. Zenker's 

 fluid can be employed. 



Salmonella, Flagella of non-motile, Ed- 

 wards, P. R., Moran, A. B. and Bruner, 

 D. W., Proc. Soc. Exp. Biol. & Med., 

 1946, 62, 296-298. 



Samarium, see Atomic Weights. 



Sandarac mixed with dioxan, camphor and 

 salol is recommended by McClung 

 (p. 40) as a mounting medium in place 

 of balsam. 



Sandison's Technique for inserting trans- 

 parent chambers in rabbit ears (Sandi- 

 son, J. C, Anat. Rec, 1924, 28, 281). 

 This has been improved by Clark, E. R. 

 et al., Anat. Rec, 1930, 47, 187-211 and 



