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Lugol's Iodine, also known as Lugol's Solution, first made in 1829, is a solution of elemental iodine and potassium iodide in water, named after the French physician J.G.A. Lugol. Lugol's iodine solution is often used as an antiseptic and disinfectant, for emergency disinfection of drinking water, and as a reagent for starch detection in routine laboratory and medical tests. These uses are possible since the solution is a source of effectively free elemental iodine, which is readily generated from the equilibrium between elemental iodine molecules and triiodide ion in the solution. Lugol's Solution has been used more rarely to replenish iodine deficiency.〔Higdon, J. (April, 2003) ("Micronutrient Information Center: Iodine," ) Linus Pauling Institute/Oregon State University (revised by Drake, V.J., July, 2007).〕 Likewise, in the Chernobyl disaster some Lugol's solution was used as an emergency source of iodide to block radioactive iodine uptake, simply because it was widely available as a drinking water decontaminant, and pure potassium iodide without iodine (the preferred agent) was not available. Since the 1970s Lugol's Solution has been available in tablet form, generally buffered. However, compounding chemists (pharmacists) had probably been creating tablets containing Lugol's Solution since the early 1900s. The tablet form is generally known as Idoral. == Applications == *As a mordant when performing a Gram stain. It is applied for 1 minute after staining with crystal violet, but before ethanol to ensure that gram positive organisms' peptidoglycan remains stained, easily identifying it as a gram positive in microscopy. *This solution is used as an indicator test for the presence of starches in organic compounds, with which it reacts by turning a dark-blue/black. Elemental iodine solutions like Lugol's will stain starches due to iodine's interaction with the coil structure of the polysaccharide. Starches include the plant starches amylose and amylopectin and glycogen in animal cells. Lugol's solution will not detect simple sugars such as glucose or fructose. In the pathologic condition amyloidosis, amyloid deposits (i.e., deposits that stain like starch, but are not) can be so abundant that affected organs will also stain grossly positive for the Lugol reaction for starch. *It can be used as a cell stain, making the cell nuclei more visible and for preserving phytoplankton samples. *During colposcopy, Lugol's iodine is applied to the vagina and cervix. Normal vaginal tissue stains brown due to its high glycogen content, while tissue suspicious for cancer does not stain, and thus appears pale compared to the surrounding tissue. Biopsy of suspicious tissue can then be performed. This is called a Schiller's test. *Lugol's iodine may also be used to better visualize the mucogingival junction in the mouth. Similar to the method of staining mentioned above regarding a colposcopy, alveolar mucosa has a high glycogen content that gives a positive iodine reaction vs. the keratinized gingiva.〔Han, J. Changes in Gingival Dimensions Following Connective Tissue Grafts for Root Coverage: Comparison of Two Procedures. ''J Perio'' 2008;79:1346-1354.〕 *Lugol's solution can also be used in various experiments to observe how a cell membrane uses osmosis and diffusion. *Lugol's iodine may also be used as an oxidizing germicide, however it is somewhat undesirable in that it may lead to scarring and discolors the skin temporarily. One way to avoid this problem is by using a solution of 70% ethanol to wash off the iodine later. *Lugol's solution is also used in the marine aquarium industry. Lugol's solution provides a strong source of free iodine and iodide to reef inhabitants and macroalgae. Although the solution is thought to be effective when used with stony corals, systems containing xenia and soft corals are assumed to be particularly benefited by the use of Lugol's solution. Used as a dip for stony and soft or leather corals, Lugol's may help rid the animals of unwanted parasites and harmful bacteria. The solution is thought to foster improved coloration and possibly prevent bleaching of corals due to changes in light intensity, and to enhance coral polyp expansion. The blue colors of ''Acropora'' spp. are thought to be intensified by the use of potassium iodide. Specially packaged supplements of the product intended for aquarium use can be purchased at specialty stores and online. * Preoperative administration of Lugol's solution decreases intraoperative blood loss during thyroidectomy in patients with Grave's disease. However, it appears ineffective in patients who are already euthyroid on anti-thyroid drugs and levothyroxine. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lugol's iodine」の詳細全文を読む スポンサード リンク
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