Strong Iodine Tincture
»Strong Iodine Tincture contains,in each 100mL,not less than 6.8g and not more than 7.5g of iodine (I),and not less than 4.7g and not more than 5.5g of potassium iodide (KI).
Strong Iodine Tincture may be prepared by dissolving 50g of Potassium Iodide in 50mLof Purified Water,adding 70g of Iodine,and agitating until solution is effected,and then adding Alcohol to make the product measure 1000mL.
Packaging and storage— Preserve in tight,light-resistant containers.
Identification—
A: Add 1drop to a mixture of 1mLof starch TSand 9mLof water:a deep blue color is produced.
B: Evaporate a few mLon a steam bath to dryness:the residue responds to the flame test for Potassium á191ñand to the tests for Iodide á191ñ.
Alcohol content á611ñ: between 82.5%and 88.5%of C2H5OH.
Assay for iodine— Proceed as directed in the Assay for iodineunder Strong Iodine Solution,using 10mLof Strong Iodine Tincture.
Assay for potassium iodide— Proceed as directed in the Assay for potassium iodideunder Strong Iodine Solution,using 10mLof Strong Iodine Tincture.The difference between the number of mLof 0.05Mpotassium iodate used and half the number of mLof 0.1Nsodium thiosulfate used in the Assay for iodine,multiplied by 16.60,represents the number of mg of KIin the volume of Strong Iodine Tincture taken.
Auxiliary Information— Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1030
Phone Number:1-301-816-8394