Natriumjodide

Natriumjodide, commonly known as sodium iodide, is a chemical compound with the formula NaI. It consists of sodium cations and iodide anions and forms a white, crystalline solid that is highly soluble in water and highly hygroscopic, gradually absorbing moisture from the air.

Sodium iodide has a relatively high melting point and is stable at room temperature. It readily participates in redox chemistry, in particular undergoing oxidation of the iodide to iodine by strong oxidizers. It is stable in ordinary conditions but must be kept dry due to its hygroscopic nature.

Applications are diverse. In medicine, sodium iodide solutions are used as a source of iodide for supplementation and, in nuclear medicine, as a carrier for radioactive iodine used in diagnostic imaging or therapy. In radiation detection, sodium iodide doped with thallium (NaI(Tl)) serves as a common scintillation crystal for gamma-ray detectors. In organic synthesis, NaI acts as a source of iodide for substitution reactions (Finkelstein-type reactions) and as an iodinating reagent in certain processes.

Production typically involves the reaction of sodium with iodine or the neutralization of hydriodic acid salts. The compound is widely manufactured for both industrial and medical uses and is often supplied as a dry powder or as a solution.

Safety and handling require attention to its hygroscopic nature; it should be stored in a tightly closed, dry container. It can cause irritation to skin and eyes, and ingestion or inhalation of dust should be avoided. Prolonged exposure to iodide can influence thyroid function due to the body’s uptake of iodide.