{"id":3914,"date":"2025-09-07T00:43:28","date_gmt":"2025-09-07T00:43:28","guid":{"rendered":"https:\/\/modafinil.pl\/?post_type=product&p=3914"},"modified":"2026-10-03T06:04:24","modified_gmt":"2026-10-03T06:04:24","slug":"potassium-iodide","status":"publish","type":"product","link":"https:\/\/modafinil.pl\/en\/sklep\/potassium-iodide\/","title":{"rendered":"Potassium Iodide (KI) (CAS 7681-11-0) \u2014 chemical reagent 1000 mg, purity \u2265 99.0%"},"content":{"rendered":"

Potassium iodide (KI)<\/strong>, an inorganic potassium salt of hydroiodic acid, white or colorless hygroscopic crystals or granular powder, 1000 mg package. Material intended exclusively for in vitro laboratory and analytical research<\/strong>. The product is not intended for human or animal consumption<\/strong>, is not a medicinal product, dietary supplement, food, or cosmetic.<\/p>\n

Three distinct entities that must not be confused<\/h2>\n

This molecule requires separating layers for a different reason than most of our catalog: potassium iodide is not a modern compound designed in a pharmaceutical laboratory, but an inorganic salt that has been widely used for decades, present simultaneously in analytical chemistry, industry, and medicine. Three contexts, three entirely different legal statuses:<\/p>\n\n\n\n\n\n\n\n
Separating the layers: substance \u2014 medicinal product \u2014 reagent<\/caption>\n
Entity<\/th>\nWhat it is<\/th>\nStatus of potassium iodide<\/th>\n<\/tr>\n<\/thead>\n
Chemical substance
potassium iodide, CAS 7681-11-0<\/th>\n		A chemical concept \u2014 an ionic salt composed of a potassium cation and an iodide anion. By itself it is neither a drug nor a reagent; its status is conferred only by the form in which it is manufactured and approved.<\/td>\ninorganic chemistry, substance registries<\/td>\n<\/tr>\n
Medicinal products
preparations for iodine prophylaxis and thyroid blocking<\/th>\n		Pharmaceutical preparations: a defined pharmaceutical form (tablets, solution), manufacturing under GMP, registration documentation, distribution within national radiological protection programs. The PubChem registry (CID 4875) links this CAS number to the names of registered pharmaceutical products for thyroid blocking with stable iodine, including Thyrosafe, Thyroshield, Iosat, Pima, Thyro-Block, Kisol, Joptone, Potide<\/strong> \u2014 and to Lugol’s solution, used in medicine since the 19th century.<\/td>\nthe public health programs and clinical literature<\/strong> cited below pertain to this entity<\/td>\n<\/tr>\n
Chemical reagent
the material offered here<\/th>\n		Material for laboratory and analytical work. It does not have, and cannot have, approval for use in humans or animals<\/strong> \u2014 it has no pharmaceutical pharmaceutical form or medicinal product documentation.<\/td>\nanalytics, chemistry, reference standards<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

The consequence is unambiguous.<\/strong> The data and publications cited further on this page, concerning iodine prophylaxis, thyroid blocking in the event of radioactive iodine-131 contamination, or iodization of table salt, refer exclusively to registered medicinal products or to public health programs conducted using them<\/strong>. None of these applications applies to the analytical reagent<\/strong>, and none of these results carries over to the offered material. The reagent is not the form in which this substance is administered to humans, and cannot be used in that way.<\/p>\n

Reagent identification card<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Registry data and identifiers \u2014 potassium iodide<\/caption>\n
Systematic name (IUPAC)<\/th>\npotassium iodide<\/td>\n<\/tr>\n
Common name<\/th>\npotassium iodide (KI)<\/td>\n<\/tr>\n
CAS number<\/th>\n7681-11-0<\/td>\n<\/tr>\n
Molecular formula<\/th>\nKI<\/td>\n<\/tr>\n
Molar mass<\/th>\n166.00 g\u00b7mol\u22121<\/sup><\/td>\n<\/tr>\n
Monoisotopic mass<\/th>\n165.8682 Da<\/td>\n<\/tr>\n
InChIKey<\/th>\nNLKNQRATVPKPDG-UHFFFAOYSA-M<\/td>\n<\/tr>\n
SMILES<\/th>\n[K+].[I-]<\/td>\n<\/tr>\n
PubChem CID<\/th>\n4875<\/a><\/td>\n<\/tr>\n
ChEMBL<\/th>\nCHEMBL3672512<\/a><\/td>\n<\/tr>\n
Form<\/th>\nwhite, colorless, hygroscopic crystals or granular powder<\/td>\n<\/tr>\n
Solubility<\/th>\nvery good in water (approx. 1 g \/ 0.7 ml water at 25\u00b0C), good in glycerol, poor in ethanol<\/td>\n<\/tr>\n
Density<\/th>\n3.13 g\/cm3<\/sup><\/td>\n<\/tr>\n
Melting point<\/th>\n681 \u00b0C<\/td>\n<\/tr>\n
Boiling point<\/th>\n1323 \u00b0C<\/td>\n<\/tr>\n
Purity<\/th>\n\u2265 99.0%<\/td>\n<\/tr>\n
Intended use<\/th>\nresearch reagent \u2014 not for human or animal consumption<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

A simple salt with two centuries of applications<\/h2>\n

Potassium iodide differs from most entries in our catalog in that it cannot be described as a link in a single research lineage. It is not an organic molecule designed and modified by one team within a single decade \u2014 it is a simple ionic salt, known to chemists for nearly two hundred years, which independently took root in several distinct fields: analytical chemistry, the photographic industry, iodine deficiency prophylaxis, and radiological protection. We state this plainly because the \u201cfrom discovery to today’s laboratory\u201d narrative template, appropriate for synthetic compounds, does not fit here \u2014 the history of this salt is multi-track, not linear.<\/p>\n

From molecular iodine to the iodide salt<\/h3>\n

The starting point is the discovery of elemental iodine \u2014 Bernard Courtois isolated it in 1811 from the ash of seaweed during saltpeter production. Potassium iodide, as a salt of hydroiodic acid, entered chemical and medical practice shortly afterward. In 1829, the French physician Jean Lugol developed a solution of iodine in an aqueous potassium iodide solution \u2014 the iodide plays a purely auxiliary role there, increasing the solubility of poorly water-soluble molecular iodine by forming the soluble triiodide ion. This same mechanism, described further in the chemistry section, underlies the classical iodometric methods still used today.<\/p>\n

Four independent paths of application<\/h3>\n

From the mid-19th century, potassium iodide developed in parallel across four unrelated contexts: as a redoximetric reagent in the then-emerging field of analytical chemistry, as a component of light-sensitive photographic emulsions (reacting with silver nitrate to form silver iodide), as a public health tool in table salt iodization programs against endemic goiter, and \u2014 from the second half of the 20th century \u2014 as an agent blocking thyroid uptake of radioactive iodine-131 in cases of radiological contamination. We describe the last of these contexts in more detail below, since it carries the greatest risk of confusing the reagent with a registered medicinal product.<\/p>\n

Timeline<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Timeline: from the discovery of iodine to modern radiological protection<\/caption>\n
1811<\/th>\nBernard Courtois isolates elemental iodine from the ash of seaweed<\/td>\n<\/tr>\n
1829<\/th>\nJean Lugol develops a solution of iodine in potassium iodide for medical use [13<\/a>]<\/td>\n<\/tr>\n
2nd half of the 19th c.<\/th>\ndevelopment of classical iodometric methods in analytical chemistry based on oxidation of the iodide ion<\/td>\n<\/tr>\n
turn of the 19th\/20th c.<\/th>\napplication in the photographic industry as a precursor of light-sensitive silver iodide<\/td>\n<\/tr>\n
1920s<\/th>\nfirst national table salt iodization programs against endemic goiter<\/td>\n<\/tr>\n
1968<\/th>\npublication of a 16-year study of iodide prophylaxis in Tasmania, WHO Bulletin [11<\/a>]<\/td>\n<\/tr>\n
1983<\/th>\nFDA update on the use of potassium iodide as a thyroid-blocking agent in radiation accidents [9<\/a>]<\/td>\n<\/tr>\n
1985<\/th>\npublication of criteria for administering KI for thyroid blocking in radioiodine contamination [8<\/a>]<\/td>\n<\/tr>\n
1996<\/th>\nassessment of potassium iodide content in Polish table salt, Roczniki PZH [12<\/a>]<\/td>\n<\/tr>\n
1986 \/ 2011<\/th>\nthe Chernobyl and Fukushima accidents renew international attention to the role of potassium iodide in radiological protection<\/td>\n<\/tr>\n
2016<\/th>\nsystematic review of the effects of iodine blocking after nuclear accidents, Journal of Radiological Protection [10<\/a>]<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Four fields, one molecule<\/h2>\n

Unlike the organic compounds in our catalog, whose literature arose in one or a few related research centers, the literature on potassium iodide is scattered across fields that rarely intersect.<\/p>\n