Elaedin

Elaedin (from Greek elaion-oil), the name given by Ranvier to an oily substance that turns black with osmic acid, which he described in the granular and clear layers of the skin; in the first in the form of small droplets among the grains of keratogalia, in the second in the form of accumulations of greater size, sometimes filling the whole cell (diffuse Elaedin). Later research (Ciliano, 1908) showed that Elaedin has no relation to fats and represents an albumin; it is soluble in water, glycerin, ammonia, in excess hydrochloric and acetic acids, insoluble in NaCl, gasoline, chloroform, ether, coagulates from alcohol and does not stain with Sudan and osmic acid; it dyes well with acid dyes. Elaedin was formerly considered a precursor of keratin, and at present a byproduct of the process of keratinization (Unna) along with keratogalia, glycogen, and oleic acid, which gives the reaction with osmium (see Keratogalia and Skin).