The document discusses the physical and chemical properties of iodine and its role in human physiology, particularly in thyroid hormone synthesis. It outlines iodine's preparation, uses as a medicinal and analytical agent, and the importance of maintaining safe storage conditions. Additionally, it covers sodium iodide and radioactive iodine, including their properties, assays, and therapeutic applications in thyroid-related disorders.

1. OFFICIAL COMPOUNDS OF IODINE
Presented By
Ms. Monika P. Maske
M. Pharm
(Pharmaceutical Chemistry)
Kamla Nehru College of Pharmacy,
Butibori, Nagpur

2. IODINE
Introduction
o Iodine (as iodide) is one of essential trace element.
o Iodide with food after absorption reaches blood circulation.
o Play important role in synthesis of two important thyroid
hormones known as thyroxine & triiodothyronine.
o Its essential for the normal growth & development
o Play a important role in energy metabolism

3. STRUCTURE OF THYROXINE &
TRIIODOTHYRONINE

4. IODINE
o Thyroxine important function is to increase the metabolic rate
by increasing the oxidative process.
o Deficiency of thyroid causes “hypothyroidism”, Cretinism.
o Metabolic processes are slowed down & gaiter characterised
by swelling of neck.
o Male usual requirement of iodine is about 140 micrograms &
female about 100 microgram daily usually obtained from diet.

5. IODINE

6. IODINE
o After internal administered iodide is oxidised to iodine.
o Then converted to an amino acid tyrosine to form monoiodo and
diiodo tyrosine.
o It again converted to triodo and tetraiodo tyrosine by coupling
reactions.
o Using radioactive iodide, iodine is incorporated in thyroid gland only
for forming the thyroid hormones.

7. IODINE
1. Physical properties:
o Symbol- I2
o Mol. weight- 253.8
o Colour- Bluish-black rhombic prism or plates
o Odour- Irritating odour
o Taste- Pungent tase
o Solubility- Insoluble in water
- soluble in alcohol, freely soluble in chloroform,
ether

8. IODINE
2. Chemical Properties:-
o At higher temperature iodine gets melt.
o It combines directly with non-metals & with many metals.
2P + 3I2 2PI2
o Reducing agents react with aqueous iodine solution & gets
oxidised.
H2S + I2 2 HI + S

9. IODINE
o Iodine react with alkali to form iodide & iodate especially when
heated.
3I2 + 6NaOH 5NaI + NaIO3 + 3H2O
o Potassium iodine dissolves in iodine because of formation of
ion
KI + I2 KI3
o Iodine add to unsaturated compounds & unsaturated acids
present in oil.
o This principal reaction used in the preparation of non-staining
iodine ointment.

10. PREPARATION
o Iodine mfg. by extracting kelp (seaweed ash) with water, the
solution is concentrated.
o The sodium and potassium are crystals out.
o leaving freely soluble sodium & potassium iodide in the
mother liquor.
o Sulphuric acid is added to mother liquor & sulphur allowed to
settle.

11. PREPARATION
2NaI + 3H2SO4 + MnO2 MnSO4 + 2NaHSO4 + 2 NaHSO4 + I2 + 2H2O
o Impurities like ICl, IBr, and ICN are removed by heating crude iodine with
potassium iodide.
ICl + KI KCl + I2

12. ASSAY
o Iodine is analysed by oxidation-reduction method.
o 0.5 g of iodine + potassium iodide + 5 ml of water +
dissolved +dilute with 50 ml of water.
o Acidify with 1 ml of acetic acid + using starch as indicator.
oTitrated with 0.1 N sodium thiosulphate solution.

13. USES
o Used as germicide and fungicide
o Powerful bactericidal
o Disinfectant of skin, mouth
o Management of burns and cuts
o Locating agent
o Treatment of thyrotoxicosis
o Purification of drinking water
o Chemical antidote for alkaloidal poising
o Analytical chemistry

14. INCOMPATIBILISM AND
STORAGE
o Iodine is oxidising agent, it oxidised hypophosphite,
sulphites, some metals.
It react with ammonia or ammoniated mercury to form
explosive iodise of nitrogen.
Storage
o iodine is stored in amber-coloured bottles with a
tight stopper and kept in cool place.

15. COMPOUND CONTAINING
IODINE
A. Sodium iodide
1. Physical properties:-
Symbol- NaI
Mol. weight- 149.9
Colour- Colourless crystals or white crystalline powder
Odour- Odourless
Nature- Hygroscopic
Solubility- Soluble in water & alcohol

16. SODIUM IODIDE
2. Chemical properties:-
o Its stable in dry air but may decompose on storage & develop
brown colour.
o The aqueous solution gives yellow ppt. with sliver nitrate.
NaI + AgNO3 AgI + NaN3

17. PREPARATION
o Take slightly excess amount of iodine + conc. of sodium
hydroxide.
it gives the mixture of sodium iodate & potassium iodate.
o The reaction mixture evaporate to dryness.
o Residue is treated with carbon to convert sodium iodate into
sodium iodide.
6 NaOH + 3 I2 5 NaI + NaIO3 + 3H2O
NaIO3 + 3C NaI + 3CO

18. ASSAY
o 1.3 g of sodium iodide + 100 ml of water.
o 20 ml of this solution + 40 ml concentrated HCl mixed
properly.
o Titrated with 0.05 M potassium iodate until colour changes to
yellow.
o 5 ml of chloroform is added with continues stirring.

19. POTASSIUM IODIDE
Incompatibilities:-
both iodides get decomposed in presence of acid with
liberation of iodine.
Storage:-
sodium and potassium iodide stored in well closed
container and kept in dry place.

20. USES
o Used in treatment of thyroid gland
o Fibrolytic agent in syphilis and leprosy
o In fungal infection & actinomycosis
o As expectorant
o In asthma and chronic bronchitis

21. RADIOACTIVE IODINE &
SODIUM IODIDE
Introduction:-
o 131I is obtained by neutron irradiation of tellurium.
o Its used in the form of sodium iodide (131I).
o In 1988 sodium iodide (131I ) official in B.P.
o 131I in the form of sodium iodide and contains sodium thiosulphate or any other
reducing agent and may be suitably buffered.

22. RADIOACTIVE IODINE &
SODIUM IODIDE
1. Properties:-
o Colour- Clear colourless solution
o 131I having half life of 8.04 days
o It emits beta and gamma radiations
o pH between 7 – 10

23. ASSAY
o The activity is determined by comparison with a standardised iodine
– 131 solution.
o Using counting instrument.
o Its also tested for radionuclide purity and Radiochemical purity.

24. USES
o Radioactive iodine is most widely used for diagnosis of thyroid
function for treatment of hyperthyroidism.
o Thyroid cancer
o Diagnosis of hypothyroidism, hyperthyroidism and goitre.
o Grave’s disease