IODOLENE AND THE SOLUBILITY OF IODIN IN LIQUID PETROLATUM

The Council on Pharmacy and Chemistry was asked to examine a preparation submitted with the statement that it was “iodin crystals incorporated in a petroleum product.” The name “Iodolene” was proposed by the promoters, providing the product was found eligible for New and Non­official Remedies.

Iodolene was stated to have been prepared by treating a liquid petrolatum, obtained from Gulf Coast petroleum, with an excess of iodin; the mixture was subsequently “placed in an oven for three hours.” The claim was made that this method of procedure produced a preparation containing more iodin than market specimens which had been examined, namely: “over 1.50 per cent. free iodine.”

Two specimens of the product were submitted, one stated to have been unfiltered, and the other filtered. Both of the specimens emitted a strong odor of hydrogen sulphide upon removing the stopper from the respective containers.

Iodin Content of Iodolene.—The iodin content of the filtered specimen was determined thus: A weighed amount—3 to 5 gm.—was transferred to a separator by means of 20 c.c. of ligroin, used in portions. Twenty c.c. of 10 per cent. potassium iodid solution was added and the free iodin titrated with tenth-normal sodium thiosulphate solution (with agitation), the end point being the absence of a yellow color in the aqueous layer. The amount of free iodin was found to be 1.32 per cent.

The Solubility of Iodin in Liquid Petrolatum.—To determine the solubility of iodin in Liquid Petrolatum, 200 c.c. of Liquid Petrolatum-Squibb (said to be composed of hydrocarbons of the naphthene series) and 200 c.c. of Stanolind Liquid Paraffin (said to be composed chiefly of marsh gas hydrocarbons) were each treated with 5 gm. of iodin crystals. The two mixtures were maintained for a week at a temperature somewhat above that of the room and agitated occasionally. Each was then cooled to room temperature (about 22 C.), agitated for a day and then filtered. The amount of iodin in the preparation made with Liquid Petrolatum-Squibb was found to be 1.42 per cent. The iodin content of the preparation made with Stanolind Liquid Paraffin was 1.30 per cent.

In view of these findings the prospective manufacturer was advised that the Council cannot countenance a proprietary name for an unofficial, simple solution of iodin in liquid petrolatum.—(From Reports A. M. A. Chemical Laboratory, 1917, p. 87.)