Free Iodin.—A weight of 6.2936 gm. was dissolved in chloroform and the solution shaken with 25 c.c. of a solution of potassium iodid. The iodin which passed into the potassium iodid solution was titrated with tenth-normal sodium thiosulphate, 0.81 c.c. being required. This indicates 0.01022 gm. of iodin, or 0.16 per cent.
Total Iodin.—Total iodin was determined by Method 1 as given above under Iodex. A weight of 4.466 gm. required 32.93 c.c. of tenth-normal sodium thiosulphate, equivalent to 0.06964 gm. of iodin, or 1.55 per cent. In a duplicate, 5 gm. of material required 33.3 c.c. of tenth-normal sodium thiosulphate, equivalent to 0.7043 gm. of iodin, or 1.41 per cent.; average, 1.48 per cent. of iodin.
Liquid Iodex, then, contains but little (0.16 per cent.) free iodin and only about three fifths of the total iodin claimed.
I. G. O.
I. G. O. is an iodin ointment. It is said to be made by Dr. H. S. Lambdin, Peru, Kansas. In a circular distributed by the manufacturer, it is stated that “I. G. O. is a saturated solution of Iodine Gas in petrolatum at 130 degrees with oil of eucalyptus. The heat of the body liberates the iodine and it is absorbed as free iodine.”
A sample of I. G. O., received from a physician, was examined. It was found to be a black ointment, green in thin layers, with a slight odor like crude petroleum. By the methods used for the examination of Iodex, I. G. O. was found to contain 0.59 per cent. of free iodin.—(From Reports A. M. A. Chemical Laboratory, 1919, p. 104.)
IODIN IN LIQUID PETROLATUM
A. H. Clark, Ph.G., Sc.B.
Of all the things used in medicine nothing seems to have attracted the attention of all classes of users as has iodin. Perhaps more romantic schemes for the cure of all the ills which afflict mankind have centered in iodin therapy than in any other one drug. Iodin is being used in every conceivable way from crystals to colloid; in vapor; combined as iodid, iodate and the like; organic, inorganic, simple and complex; internal, external and by injection, and yet there seems to be no end to the ingenious schemes for its exploitation.