Scharlachrot

SCHARLACHROT (syn. Fettponceau-azo-ortho-toluol-azo-beta-naphthol), a neutral aniline azo dye prepared according to the specifications of Michaelis by the firm Kalle & Co.; a brown-red powder, insoluble in water, alkalis, acids, and glycerin, soluble in alcohol, better in chloroform, neutral fats (liquid), fatty acids, liquid and melted paraffin. Used as an excellent stain for fat, which is colored a bright red; some authors prefer Scharlachrot to Sudan III, with which it has much in common both in composition and staining technique (see Ponceau). Used as a saturated solution in 70% ethyl alcohol, preferably after formalin fixation. Herxheimer recommends an alkaline solution for more complete staining, but according to B. Fischer, this may lead to partial loss of especially small fat droplets. Fat is stained only when liquid or dissolved, therefore for staining solid fats at ordinary temperature, a thermostat should be used. In the form of 4-8% ointments, Scharlachrot is used as a remedy that promotes the growth of granulations in the healing of suppurative wounds.