• heaviest
  • This period contains technetium, one of the two elements until lead that has no stable isotopes (along with promethium), as well as molybdenum and iodine, two of the heaviest elements with a known biological role, and Niobium has the largest magnetic known penetration depth of all the elements. (wikipedia.org)
  • iodide
  • Iodine occurs in many oxidation states, including iodide (I−), iodate (IO− 3), and the various periodate anions. (wikipedia.org)
  • The inner walls of the capsule are then rinsed with dilute NaOH solution to collect iodine as soluble iodide and hypoiodite OI−, according to the standard disproportionation reaction of halogens in alkaline solutions. (wikipedia.org)
  • 125I
  • Iodine-125 (125I) is a radioisotope of iodine which has uses in biological assays, nuclear medicine imaging and in radiation therapy as brachytherapy to treat a number of conditions, including prostate cancer, uveal melanomas, and brain tumors. (wikipedia.org)
  • Iodine-125 itself has a neutron capture cross section of 900 barns, and consequently during a long irradiation, part of the 125I formed will be converted to 126I, a beta-emitter and positron-emitter with a half-life of 13.1 days, which is not medically useful. (wikipedia.org)
  • vapor
  • It was Gay-Lussac who suggested the name "iode", from the Greek word ἰοειδής (ioeidēs) for violet (because of the colour of iodine vapor). (wikipedia.org)
  • More commonly, powdered elemental tellurium is irradiated and then I-131 separated from it by dry distillation of the iodine, which has a far higher vapor pressure. (wikipedia.org)
  • isolate
  • Arguments erupted between Davy and Gay-Lussac over who identified iodine first, but both scientists acknowledged Courtois as the first to isolate the element. (wikipedia.org)
  • tissues
  • Thus, iodine-131 is increasingly less employed in small doses in medical use (especially in children), but increasingly is used only in large and maximal treatment doses, as a way of killing targeted tissues. (wikipedia.org)
  • stable
  • Irradiation of natural tellurium produces almost entirely I-131 as the only radionuclide with a half-life longer than hours, since most lighter isotopes of tellurium become heavier stable isotopes, or else stable iodine or xenon. (wikipedia.org)
  • Excesses of stable 129Xe in meteorites have been shown to result from decay of "primordial" iodine-129 produced newly by the supernovas that created the dust and gas from which the solar system formed. (wikipedia.org)
  • decay
  • Due to its mode of beta decay, iodine-131 is notable for causing mutation and death in cells that it penetrates, and other cells up to several millimeters away. (wikipedia.org)
  • Its decay is the basis of the I-Xe iodine-xenon radiometric dating scheme, which covers the first 85 million years of solar system evolution. (wikipedia.org)
  • Thereafter, the irradiated gas is allowed to decay for three or four days to dispose of short-lived unwanted isotopes, and to allow the newly created xenon-125 (half-life 17 hours) to decay to iodine-125. (wikipedia.org)
  • therapeutic
  • Iodine-131 can be "seen" by nuclear medicine imaging techniques (i.e., gamma cameras) whenever it is given for therapeutic use, since about 10% of its energy and radiation dose is via gamma radiation. (wikipedia.org)
  • Much smaller incidental doses of iodine-131 than those used in medical therapeutic procedures, are supposed by some studies to be the major cause of increased thyroid cancers after accidental nuclear contamination. (wikipedia.org)
  • All other iodine radioisotopes have half-lives less than 60 days, and four of these are used as tracers and therapeutic agents in medicine. (wikipedia.org)
  • radiation
  • Regulation of autophagy via PERK-eIF2α effectively relieve the radiation myelitis induced by iodine-125. (nih.gov)
  • By contrast, other iodine radioisotopes are usually created by far more expensive techniques, starting with reactor radiation of expensive capsules of pressurized xenon gas. (wikipedia.org)
  • Iodine-125 has been used in scanning/imaging the thyroid, but iodine-123 is preferred for this purpose, due to better radiation penetration and shorter half-life (13 hours). (wikipedia.org)
  • acid
  • Iodine is also used as a catalyst in the industrial production of acetic acid and some polymers. (wikipedia.org)
  • methods
  • The low-cost availability of I-131, in turn, is due to the relative ease of creating I-131 by neutron bombardment of natural tellurium in a nuclear reactor, then separating I-131 out by various simple methods (i.e., heating to drive off the volatile iodine). (wikipedia.org)