Sodium iodide is a white, crystalline salt with
chemical formulaA chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....
NaSodium is a metallic element with a symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals within "group 1"...
IIodine , is a chemical element that has the symbol I and atomic number 53. Naturally-occurring iodine is a single isotope with 74 neutrons....
used in radiation detection, treatment of
iodine deficiencyIodine is an essential trace element; the thyroid hormones thyroxine and triiodotyronine contain iodine. In areas where there is little iodine in the diet—typically remote inlandareas where no marine foods are eaten—iodine deficiency gives rise to...
, and as a reactant in the
Finkelstein reactionThe Finkelstein reaction, named for the German chemist Hans Finkelstein , is an S
N2 reaction that involves the exchange of one halogen atom for another...
.
Sodium iodide is commonly used to treat and prevent
iodine deficiencyIodine is an essential trace element; the thyroid hormones thyroxine and triiodotyronine contain iodine. In areas where there is little iodine in the diet—typically remote inlandareas where no marine foods are eaten—iodine deficiency gives rise to...
.
Sodium iodide is used in
polymerase chain reactionIn molecular biology, the polymerase chain reaction is a technique to amplify a single or few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence...
s, and also (as an
acetoneAcetone is the organic compound with the formula OC2. This colorless, mobile, flammable liquid is the simplest example of the ketones. Owing to the fact that acetone is miscible with water it serves as an important solvent in its own right, typically as the solvent of choice for...
solution) in the
Finkelstein reactionThe Finkelstein reaction, named for the German chemist Hans Finkelstein , is an S
N2 reaction that involves the exchange of one halogen atom for another...
, for conversion of an alkyl chloride into an alkyl iodide. This relies on the insolubility of
sodium chlorideSodium chloride, also known as salt, common salt, table salt, or halite, is an ionic compound with the formula NaCl. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multicellular organisms...
in
acetoneAcetone is the organic compound with the formula OC2. This colorless, mobile, flammable liquid is the simplest example of the ketones. Owing to the fact that acetone is miscible with water it serves as an important solvent in its own right, typically as the solvent of choice for...
to drive the reaction.
- R- + → R- +
Sodium iodide crystals doped with
thalliumThallium is a chemical element with the symbol Tl and atomic number 81. This soft gray malleable poor metal resembles tin but discolors when exposed to air. Approximately 60-70% of thallium production is used in the electronics industry, and the rest is used in the pharmaceutical industry and in...
, NaI(Tl), when subjected to ionizing radiation, emit
photonIn physics, a photon is an elementary particle, the quantum of the electromagnetic field and the basic "unit" of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...
s (i.e.,
scintillateScintillation can refer to:*Scintillation , the play of light off the faceted surfaces of gemstones*Scintillation , atmospheric effects which influence astronomical observations...
) and are used in scintillation detectors, traditionally in
nuclear medicineNuclear medicine is a branch or specialty of medicine and medical imaging that uses radioactive isotopes and relies on the process of radioactive decay in the diagnosis and treatment of disease. In nuclear medicine procedures, radionuclides are combined with other chemical compounds or...
,
geophysicsGeophysics, a major discipline of the Earth sciences and a subdiscipline of physics, is the study of the whole Earth by the quantitative observation of its physical properties. Geophysical data are used in academics to observe tectonic plate motions, study the internal structure of the Earth,...
,
nuclear physicsNuclear physics is the field of physics that studies the building blocks and interactions of atomic nuclei.The most commonly known applications of nuclear physics are nuclear power and nuclear weapons, but the research has provided wider applications, including those in medicine , materials...
, and environmental measurements.
Sodium iodide is a white, crystalline salt with
chemical formulaA chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....
NaSodium is a metallic element with a symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals within "group 1"...
IIodine , is a chemical element that has the symbol I and atomic number 53. Naturally-occurring iodine is a single isotope with 74 neutrons....
used in radiation detection, treatment of
iodine deficiencyIodine is an essential trace element; the thyroid hormones thyroxine and triiodotyronine contain iodine. In areas where there is little iodine in the diet—typically remote inlandareas where no marine foods are eaten—iodine deficiency gives rise to...
, and as a reactant in the
Finkelstein reactionThe Finkelstein reaction, named for the German chemist Hans Finkelstein , is an S
N2 reaction that involves the exchange of one halogen atom for another...
.
Uses
Sodium iodide is commonly used to treat and prevent
iodine deficiencyIodine is an essential trace element; the thyroid hormones thyroxine and triiodotyronine contain iodine. In areas where there is little iodine in the diet—typically remote inlandareas where no marine foods are eaten—iodine deficiency gives rise to...
.
Sodium iodide is used in
polymerase chain reactionIn molecular biology, the polymerase chain reaction is a technique to amplify a single or few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence...
s, and also (as an
acetoneAcetone is the organic compound with the formula OC2. This colorless, mobile, flammable liquid is the simplest example of the ketones. Owing to the fact that acetone is miscible with water it serves as an important solvent in its own right, typically as the solvent of choice for...
solution) in the
Finkelstein reactionThe Finkelstein reaction, named for the German chemist Hans Finkelstein , is an S
N2 reaction that involves the exchange of one halogen atom for another...
, for conversion of an alkyl chloride into an alkyl iodide. This relies on the insolubility of
sodium chlorideSodium chloride, also known as salt, common salt, table salt, or halite, is an ionic compound with the formula NaCl. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multicellular organisms...
in
acetoneAcetone is the organic compound with the formula OC2. This colorless, mobile, flammable liquid is the simplest example of the ketones. Owing to the fact that acetone is miscible with water it serves as an important solvent in its own right, typically as the solvent of choice for...
to drive the reaction.
- R- + → R- +
Sodium iodide crystals doped with
thalliumThallium is a chemical element with the symbol Tl and atomic number 81. This soft gray malleable poor metal resembles tin but discolors when exposed to air. Approximately 60-70% of thallium production is used in the electronics industry, and the rest is used in the pharmaceutical industry and in...
, NaI(Tl), when subjected to ionizing radiation, emit
photonIn physics, a photon is an elementary particle, the quantum of the electromagnetic field and the basic "unit" of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...
s (i.e.,
scintillateScintillation can refer to:*Scintillation , the play of light off the faceted surfaces of gemstones*Scintillation , atmospheric effects which influence astronomical observations...
) and are used in scintillation detectors, traditionally in
nuclear medicineNuclear medicine is a branch or specialty of medicine and medical imaging that uses radioactive isotopes and relies on the process of radioactive decay in the diagnosis and treatment of disease. In nuclear medicine procedures, radionuclides are combined with other chemical compounds or...
,
geophysicsGeophysics, a major discipline of the Earth sciences and a subdiscipline of physics, is the study of the whole Earth by the quantitative observation of its physical properties. Geophysical data are used in academics to observe tectonic plate motions, study the internal structure of the Earth,...
,
nuclear physicsNuclear physics is the field of physics that studies the building blocks and interactions of atomic nuclei.The most commonly known applications of nuclear physics are nuclear power and nuclear weapons, but the research has provided wider applications, including those in medicine , materials...
, and environmental measurements. NaI(Tl) is the most widely used scintillation material and has the highest light output. The crystals are usually coupled with a
photomultiplierPhotomultiplier tubes , members of the class of vacuum tubes, and more specifically phototubes, are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum...
tube, in a hermetically sealed assembly, as sodium iodide is hygroscopic. Fine-tuning of some parameters (i.e., radiation hardness, afterglow,
transparencyTransparency may refer to:*Transparency , the physical property of allowing the transmission of light through a material*Transparent materials, materials which exhibit the physical property of allowing the transmission of light...
) can be achieved by varying the conditions of the crystal growth. Crystals with a higher level of doping are used in
X-rayX-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays...
detectors with high spectrometric quality. Sodium iodide can be used both as
single crystalA single crystal usually refers to a grain boundary free monocrystalline solid-Background and uses:A single crystal solid is a material in which the crystal lattice of the entire sample is continuous and unbroken to the edges of the sample, with no grain boundaries...
s and as polycrystals for this purpose.
The radioactive iodide salt of sodium, Na(I-131) is used to diagnose
thyroid cancerThyroid neoplasm or thyroid cancer usually refers to any of four kinds of malignant tumors of the thyroid gland: papillary, follicular, medullary or anaplastic. Most patients are 25 to 65 years of age when first diagnosed; women are more affected than men. Papillary and follicular tumors are the...
.
Solubility data
Solubility of NaI in various solvents
(g NaI / 100g of solvent at 25°C)
| H2O |
184 |
Liquid ammoniaAmmonia is a compound of nitrogen and hydrogen with the formula NH 3. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and fertilizers...
|
162 |
Liquid sulfur dioxideSulfur dioxide is the chemical compound with the formula SO 2. It is produced by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide...
|
15 |
| Methanol Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with formula CH3OH . It is toxic: drinking 10 ml will cause blindness, and as little as 100 ml will cause death...
|
62.5 - 83.0 |
| Formic acid Formic acid is the simplest carboxylic acid. Its formula is HCOOH or CH2O2. It is an important intermediate in chemical synthesis and occurs naturally, most notably in the venom of bee and ant stings.In nature, it is found in the stings and bites of many insects of the order...
|
61.8 |
| Acetonitrile Acetonitrile is the chemical compound with formula CH3CN. This colourless liquid is the simplest organic nitrile. It is produced mainly as a byproduct of acrylonitrile manufacture. It is widely used as a polar aprotic solvent in synthetic chemistry, and as a medium-polarity solvent in...
|
24.9 |
| Acetone Acetone is the organic compound with the formula OC2. This colorless, mobile, flammable liquid is the simplest example of the ketones. Owing to the fact that acetone is miscible with water it serves as an important solvent in its own right, typically as the solvent of choice for...
|
28.0 |
| Formamide Formamide, also known as methanamide, is an amide derived from formic acid. It is a clear liquid which is miscible with water and has an ammonia-like odor. It is used primarily for manufacturing sulfa drugs and synthesizing vitamins and as a softener for paper and fiber...
|
57 - 85 |
| Acetamide Acetamide , CH3CONH2, the amide of acetic acid, is a white crystalline solid in pure form. It is produced by dehydrating ammonium acetate:...
|
32.3 |
DimethylformamideDimethylformamide is the organic compound with the formula 2NCH. Commonly abbreviated DMF , this colourless liquid is miscible with water and the majority of organic liquids. DMF is a common solvent for chemical reactions...
|
3.7 - 6.4 |
| |
External links