Key Difference – Povidone Iodine vs Iodine
Despite having similar sounding names, iodine and povidone-iodine are two different compounds and a distinct difference can be noted between these two compounds based on their composition and uses. Iodine is a pure chemical element, and povidone-iodine is a product containing iodine as the main substance. The key difference between them is, Iodine is naturally available in sea water and in the earth crust whereas povidone iodine is a man- made product that contains iodine.
What is Iodine?
Iodine (I) is a chemical element in the periodic table with the atomic number 53. It is the heaviest member of the halogen group (group VII). It is found in solid form at room temperature. There are so many industrial applications of Iodine; for example, it is used as a nutrient in some food based products and in industrial production of acetic acid and some polymers. Iodine is an essential mineral for human health to produce hormones in the thyroid. Naturally, it is present in the human body in smaller amounts (about 15-20 mg). But, the required amount is greater than the present value; therefore, we need to take it from our diet.
|Life stage||Iodine required per day/ micrograms|
|Pregnant women||250 mcg|
|Breastfeeding women||250 mcg|
What is Povidone-iodine?
Povidone-iodine is an iodine based product which is used as an antiseptic solution for disinfecting minor wounds on the skin. This has been used for ages, and it is known as one of the oldest skin antiseptic solutions. Povidone iodine is designed only for external applications on the skin. But some people have side effects such as itching, swelling of the facial area and breathing difficulties.
What is the difference between Povidone Iodine and Iodine?
Definition of Povidone Iodine and Iodine
Iodine: Iodine is the chemical element of atomic number 53, a nonmetallic element forming black crystals and a violet vapor.
Providone-iodine: Povidone-iodine is an iodine based product which is used as an antiseptic solution.
Composition of Povidone Iodine and Iodine
Iodine: Iodine is a pure element, and it contains 100% iodine in its composition. It is found in solid form, grayish black small crystals with a metallic luster. Iodine can be obtained in all three forms; solid, liquid and gas. Liquid iodine is a dark purple colored solution, and iodine gas (I2) is a purple colored gas. Iodine has 37 known isotopes, but only 127I is stable.
Povidone-iodine: Povidone-iodine is a complex of iodine and povidone. It has from 9%-12% of iodine on the dry basis. The chemical formula of povidone-iodine is (C6H9NO)n·xI.
Uses of Povidone Iodine and Iodine
Iodine: Iodine has different uses in numerous areas.
- To produce antiseptics, specialized soaps, and drugs
- To produce dyes
- As a catalyst
- In food products as a nutrient
Povidone-iodine: Povidone iodine is an antiseptic solution, used as a topical ointment, shampoo or a scrub. It is applied to the skin externally; it can be on the wounded area, or an area that needs to be disinfected.
Properties of Povidone Iodine and Iodine
Iodine: Iodine slightly dissolves in water, but completely dissolves in many other solutions producing a purple colored solution.
Povidone-iodine: Povidone-iodine is fully soluble in both cold water and in warm water. It is also soluble in some other solvents such as ethyl alcohol, isopropyl alcohol, polyethylene glycol and glycerol.
Iodine: Deficiency of iodine in human body causes several health effects. It can lead to enlargement of the thyroid gland. But, those are preventable by taking the required amount of iodine. The intake of iodized salt is the most convenient method.
Povidone-iodine: Not all people are allergic to povidone—iodine, but some people have side effects such as irritation of the skin, swelling of the face and breathing problems. Because, it doesn’t particularly mention the dosage and it is just applied on the open wound or around the area that needs to be disinfected.Image Courtesy: “Sample of iodine” by LHcheM – Own work. ( CC BY-SA 3.0) via Commons “betadine-lotion” by BHVtotaal (CC BY 3.0) via iconshut.com