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Pertechnetate
The pertechnetate ion () is an oxyanion with the chemical formula . It is often used as a convenient water-soluble source of isotopes of the radioactive element technetium (Tc). In particular it is used to carry the 99mTc isotope (half-life 6 hours) which is commonly used in nuclear medicine in several nuclear scanning procedures. A technetate(VII) salt is a compound containing this ion. Pertechnetate compounds are salts of technetic(VII) acid. Pertechnetate is analogous to permanganate but it has little oxidizing power. Pertechnetate has higher oxidation power than perrhenate. Understanding pertechnetate is important in understanding technetium contamination in the environment and in nuclear waste management. Chemistry is the starting material for most of the chemistry of technetium. Pertechnetate salts are usually colorless. is produced by oxidizing technetium with nitric acid or with hydrogen peroxide. The pertechnetate anion is similar to the permanganate anion but is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technetium
Technetium is a chemical element with the symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive. All available technetium is produced as a synthetic element. Naturally occurring technetium is a spontaneous fission product in uranium ore and thorium ore, the most common source, or the product of neutron capture in molybdenum ores. This silvery gray, crystalline transition metal lies between manganese and rhenium in group 7 of the periodic table, and its chemical properties are intermediate between those of both adjacent elements. The most common naturally occurring isotope is 99Tc, in traces only. Many of technetium's properties had been predicted by Dmitri Mendeleev before it was discovered. Mendeleev noted a gap in his periodic table and gave the undiscovered element the provisional name '' ekamanganese'' (''Em''). In 1937, technetium (specifically the technetium-97 isotope) became the first predominantly artificial element to be produce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Pertechnetate
Sodium pertechnetate is the inorganic compound with the formula NaTcO4. This colourless salt contains the pertechnetate anion, . The radioactive anion is an important radiopharmaceutical for diagnostic use. The advantages to include its short half-life of 6 hours and the low radiation exposure to the patient, which allow a patient to be injected with activities of more than 30 millicuries. is a precursor to a variety of derivatives that are used to image different parts of the body. Chemistry is the starting material for most of the chemistry of technetium. Pertechnetate salts are usually colorless. is produced by oxidizing technetium with nitric acid or with hydrogen peroxide. The pertechnetate anion is similar to the permanganate anion but is a weaker oxidizing agent. It is tetrahedral and diamagnetic. The standard electrode potential for / is only +0.738 V in acidic solution, as compared to +1.695 V for /. Because of its diminished oxidizing power, is stable in alkaline so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Pertechnetate
Ammonium pertechnetate is a chemical compound with the formula NH4TcO4. It is the ammonium salt of pertechnetic acid. The most common form uses 99Tc. The compound is readily soluble in aqueous solutions forming ammonium and pertechnetate ions. It can be synthesized by the reaction of pertechnetic acid and ammonium nitrate Ammonium nitrate is a chemical compound with the chemical formula . It is a white crystalline salt consisting of ions of ammonium and nitrate. It is highly soluble in water and hygroscopic as a solid, although it does not form hydrates. It is ...: :HTcO4 + NH4NO3 → NH4TcO4 + HNO3 It thermally decomposes under inert atmosphere at 700 °C to technetium dioxide: :NH4TcO4 → TcO2 + 2 H2O + 1/2 N2 References {{Technetium compounds Pertechnetates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technetium-99m
Technetium-99m (99mTc) is a metastable nuclear isomer of technetium-99 (itself an isotope of technetium), symbolized as 99mTc, that is used in tens of millions of medical diagnostic procedures annually, making it the most commonly used medical radioisotope in the world. Technetium-99m is used as a radioactive tracer and can be detected in the body by medical equipment ( gamma cameras). It is well suited to the role, because it emits readily detectable gamma rays with a photon energy of 140 keV (these 8.8 pm photons are about the same wavelength as emitted by conventional X-ray diagnostic equipment) and its half-life for gamma emission is 6.0058 hours (meaning 93.7% of it decays to 99Tc in 24 hours). The relatively "short" physical half-life of the isotope and its biological half-life of 1 day (in terms of human activity and metabolism) allows for scanning procedures which collect data rapidly but keep total patient radiation exposure low. The same characteristics ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technetium-99m Generator
A technetium-99m generator, or colloquially a technetium cow or moly cow, is a device used to extract the metastable isotope 99mTc of technetium from a decaying sample of molybdenum-99. 99Mo has a half-life of 66 hours and can be easily transported over long distances to hospitals where its decay product technetium-99m (with a half-life of only 6 hours, inconvenient for transport) is extracted and used for a variety of nuclear medicine diagnostic procedures, where its short half-life is very useful. Parent isotope source 99Mo can be obtained by the neutron activation (n,γ reaction) of 98Mo in a high neutron flux reactor. However, the most frequently used method is through fission of uranium-235 in a nuclear reactor. While most reactors currently engaged in 99Mo production use highly enriched uranium-235 targets, proliferation concerns have prompted some producers to transition to low-enriched uranium targets. The target is irradiated with neutrons to form 99Mo as a fiss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pertechnetic Acid
Pertechnetic acid (HTcO4) is a compound of technetium that is produced by reacting technetium(VII) oxide (Tc2O7) with water or strong oxidizing acids, such as nitric acid, concentrated sulfuric acid or aqua regia. The dark red hygroscopic substance is a strong acid, with a p''K''a of 0.32, as such it exists almost entirely as the pertechnetate ion in aqueous solution. The red color in solution is thought to be due to the formation of the polyoxometallate . Use of strong enough acid solution, for example, concentrated sulfuric acid, can generate the protonated form, which then exists as the octahedral TcO3(OH)(H2O)2 di hydrate complex. See also * Sodium pertechnetate Sodium pertechnetate is the inorganic compound with the formula NaTcO4. This colourless salt contains the pertechnetate anion, . The radioactive anion is an important radiopharmaceutical for diagnostic use. The advantages to include its short ha ... References {{Technetium compounds Pertechnetates Min ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiopharmaceutical
Radiopharmaceuticals, or medicinal radiocompounds, are a group of pharmaceutical drugs containing radioactive isotopes. Radiopharmaceuticals can be used as diagnostic and therapeutic agents. Radiopharmaceuticals emit radiation themselves, which is different from contrast media which absorb or alter external electromagnetism or ultrasound. Radiopharmacology is the branch of pharmacology that specializes in these agents. The main group of these compounds are the radiotracers used to diagnose dysfunction in body tissues. While not all medical isotopes are radioactive, radiopharmaceuticals are the oldest and still most common such drugs. Drug nomenclature As with other pharmaceutical drugs, there is standardization of the drug nomenclature for radiopharmaceuticals, although various standards coexist. The International Nonproprietary Names (INNs), United States Pharmacopeia (USP) names, and IUPAC names for these agents are usually similar other than trivial style difference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formate
Formate (IUPAC name: methanoate) is the conjugate base of formic acid. Formate is an anion () or its derivatives such as ester of formic acid. The salts and esters are generally colorless.Werner Reutemann and Heinz Kieczka "Formic Acid" in ''Ullmann's Encyclopedia of Industrial Chemistry'' 2002, Wiley-VCH, Weinheim. Fundamentals When dissolved in water, formic acid converts to formate: : Formate is a planar anion. The two oxygen atoms are equivalent and bear a partial negative charge. The remaining C-H bond is not acidic. Biochemistry : Formate is a common C-1 source in living systems. It is formed from many precursors including choline, serine, and sarcosine. It provides a C-1 source in the biosynthesis of some nucleic acids. Formate (or formic acid) is ina leaving group in the demethylation of some sterols.. These conversions are catalyzed by aromatase enzymes using O2 as the oxidant. Specific conversions include testosterone to estradiol and androstenedione to e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxylamine
Hydroxylamine is an inorganic compound with the formula . The material is a white crystalline, hygroscopic compound.Greenwood and Earnshaw. ''Chemistry of the Elements.'' 2nd Edition. Reed Educational and Professional Publishing Ltd. pp. 431–432. 1997. Hydroxylamine is almost always provided and used as an aqueous solution. It is consumed almost exclusively to produce Nylon-6. It is also an intermediate in biological nitrification. The oxidation of to hydroxylamine is a step in biological nitrification. History Hydroxylamine was first prepared as hydroxylammonium chloride in 1865 by the German chemist Wilhelm Clemens Lossen (1838-1906); he reacted tin and hydrochloric acid in the presence of ethyl nitrate. It was first prepared in pure form in 1891 by the Dutch chemist Lobry de Bruyn and by the French chemist Léon Maurice Crismer (1858-1944). The coordination complex , known as Crismer's salt, releases hydroxylamine upon heating. Production Hydroxylamine or its salts can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly toxic unless handled in solution as, for example, hydrazine hydrate (). Hydrazine is mainly used as a foaming agent in preparing polymer foams, but applications also include its uses as a precursor to polymerization catalysts, pharmaceuticals, and agrochemicals, as well as a long-term storable propellant for in-space spacecraft propulsion. Additionally, hydrazine is used in various rocket fuels and to prepare the gas precursors used in air bags. Hydrazine is used within both nuclear and conventional electrical power plant steam cycles as an oxygen scavenger to control concentrations of dissolved oxygen in an effort to reduce corrosion. the world hydrazine hydrate market amounted to $350 million. About two million tons of hydrazine hydrate were used in foam blowing agents in 2015. Hydra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technetium (99mTc) Exametazime
Technetium (99mTc) exametazime is a radiopharmaceutical sold under the trade name Ceretec, and is used by nuclear medicine physicians for the detection of altered regional cerebral perfusion in stroke and other cerebrovascular diseases. It can also be used for the labelling of leukocytes to localise intra-abdominal infections and inflammatory bowel disease. Exametazime (the part without technetium) is sometimes referred to as ''hexamethylpropylene amine oxime'' or ''HMPAO'', although correct chemical names are: *(NE)-N- 3R)-3-3-(2R,3E)-3-hydroxyiminobutan-2-ylmino">3-(2R,3E)-3-hydroxyiminobutan-2-yl.html" ;"title="3R)-3-3-(2R,3E)-3-hydroxyiminobutan-2-yl">3R)-3-3-(2R,3E)-3-hydroxyiminobutan-2-ylmino2,2-dimethylpropyl]amino]butan-2-ylidene]hydroxylamine *or 3,3'-((2,2,-dimethyl-1,3-propanediyl)diimino)bis-2-butanone dioxime. Chemistry The drug consists of exametazime as a chelating agent for the radioisotope technetium-99m. Both enantiomeric forms of exametazime are used—th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
