Iodine content

Specifications and Standards, Shipping. Commercial iodine has a minimum purity of 99.8%. The Committee of Analytical reagents of the American Chemical Society (67) and the U.S. Pharmacopoeia XXII (68) specify an iodine content not less than 99.8%, a maximum nonvolatile residue of 0.01%, and chlorine—bromine (expressed as chlorine) of 0.005% (ACS) and 0.028% (USP), respectively. In the past these requirements were attained basicaHy only by sublimation, but with processing changes these specifications can be met by direct production of iodine. Previously the impurities of the Chilean product were chiefly water, sulfuric acid, and insoluble materials. Improvements in the production process, and especiaHy in the refining step, aHow the direct obtainment of ACS-type iodine. Also, because of its origin and production process, the Chilean iodine has a chlorine—bromine impurity level of no more than 0.002%. 

High Osmolality Contrast Media. An important advance in radiopaques came with the synthesis of aminotriiodoben2oic acid and its acetylated derivative, acetrizoic acid [85-36-9] (5) (8,9). Aqueous solutions of sodium acetrizoate possessed the thermal stabiUty so that they could be autoclaved (10) with minimal decomposition. The higher iodine content, ie, 3 atoms/molecule, increased the contrast efficiency, and the clinical safety of acetrizoate was improved over that of the earlier urographic agents. 

Name Company Name Molecular weight Iodine content, % Solubihty ia water, % wt /vol Viscosity, 300 mg/mL, cps... 

N Generic ame Trade Company name Mol wt Iodine content, % Concentration mg/mL Osmolahty, mOsm/kg H2O Viscosity, cps 20°C/37°C LD yiv lats, g/kg... 

When the purity of the preparation has been ascertained, both T and T are assayed on the basis of their iodine content after combustion in an oxygen flask (29,30). 

Occurrence. Iodine [7553-56-2] is widely distributed in the Hthosphere at low concentrations (about 0.3 ppm) (32). It is present in seawater at a concentration of 0.05 ppm (33). Certain marine plants concentrate iodine to higher levels than occur in the sea brine these plants have been used for their iodine content. A significant source of iodine is caUche deposits of the Atacama Desert, Chile. About 40% of the free world s iodine was produced in Japan from natural gas wells (34), but production from Atacama Desert caUche deposits is relatively inexpensive and on the increase. By 1992, Chile was the primary world producer. In the United States, underground brine is the sole commercial source of iodine (35). Such brine can be found in the northern Oklahoma oil fields originating in the Mississippian geological system (see Iodine and iodine compounds). 

In the food industry, synthetic dyes can be used also in the form of lakes obtained by precipitation of a soluble colorant onto an insoluble base. There are several insoluble bases, but only alumina is permitted for food application by FDA and EU regulation. All the synthetic food dyes can be obtained and used in food in the form of aluminium lakes, except erythrosine due to concerns about inorganic iodine content. 

The violent or explosive reactions which carbon tetrachloride, chloroform, etc., exhibit on direct local contact with gaseous fluorine [1], can be moderated by suitable dilution, catalysis and diffused contact [2], Combustion of perfluorocy-clobutane-fluorine mixtures was detonative between 9.04 and 57.9 vol% of the halocarbon [3], Iodoform reacts very violently with fluorine owing to its high iodine content [4], Explosive properties of mixtures with 1,2-dichlorotetrafluoroethane have been studied [5],... 

Truesdale [77] has described autoanalyser procedures for the determination of iodate and total iodine in seawater. The total iodine content of seawater (approximately 50-60 ig/l) is believed to be composed of iodate (30-60 xg/l of I) and iodine-iodine (0-20 xg/l) with perhaps a few ig/l of organically... 

Suppose you are analysing a number of samples of ground nutrient tablets to determine their iodine content. The method is very simple. A known mass of each sample is taken, processed to isolate the iodine,... 

In this method lg of soil is refluxed with 2M sodium hydroxide after centrifuging to remove solids. The clean extract is digested with perchloric acid-nitric acid at 265 °C. The iodine content of the extract is determined by the catalytic action of iodine on the oxidation of arsenic III ions with cerium IV ions. Between 96 and 97% recovery of added iodine spikes to soil were obtained by this method. 

The substance is burned on a platinum catalyst in a stream of oxygen and the iodine liberated is oxidised to iodic acid by bromine in acetic acid. After excess bromine has been removed with formic acid, potassium iodide is added to the solution, and the iodine liberated is titrated with thiosulphate. Since the amount of iodine titrated is six times the iodine content of the substance the method yields very accurate results. 

We have already cited evidence to indicate that iodine needs vary substantially from individual to individual. Not only does the thyroid hormone content of the blood show high inter-individual variation, but in endemic regions not all individuals exhibit simple goiter due to iodine deficiency. And, in nonendemic regions where the iodine content of the foods is sufficient for most individuals, there are still some who suffer deficiency. Furthermore, even the iodine in iodized salt is said to be sufficient to yield unfavorable results for some individuals. 

Hubl e reagent analychem Solution of iodine and mercuric chloride in alcohol used to determine the iodine content of oils and fats. hab-alz re,a- 3nt ... 

A series of iomeprol-containing liposomes were evaluated in animals by Petersein et al. [62] and in healthy volunteers by Spinazzi et al. [63,64]. BR2 and BR21 are liposomes made of phosphatidyl choline (PC),dipalmitoyl phospatidic acid (DPPA) and cholesterol at a molar ratio of 2 1 (PC -i- DPPA/cholesterol) with an iodine content of 260 mg mL (BR2) and 320 mg mL" (BR21), respectively, and a size of 0.4 pm. BR2 contains 40 mg lipid mL and BR21 20 mg mL L In rabbits, BR2 tended to provide a higher and more persistent CT enhancement than BR21. 

Adverse reactions are related to the iodine content of the drug the toxicity is often expressed as skin reactions, thyroid enlargement, and interference with thyroid function studies. Headache and diarrhea also occur. Chronic use of clioquinol, a closely related agent, has been linked to a myelitislike illness and to optic atrophy with permanent loss of vision. 

The total thyroid hormone content of thyroid glands and the ratio of T3 to T4 vary somewhat from one species to another. Thyroid USP preparations are therefore standardized on the basis of their iodine content. Much of the iodine in these preparations is in the metabolically inactive form of iodotyrosines. Thus, a given preparation may satisfy the USP iodine assay requirements and yet contain low amounts of T4 and T3. Thyrar (a beef extract) and Armour Thyroid tablets (a pork extract) are evaluated by additional biological assays to ensure consistent potency from one batch to another. 

Mel nikova, N. and V. Smirnov. 1972. Iodine contents of herbage species. Korma 5 44. 

Hemken, R. W. 1980. Milk and meat iodine content Relation to human health. J. Am. Vet. Med. Assoc. 176, 1119-1121. 

In their experiments water was the dispersed phase and toluene the continuous phase. Iodine was dissolved in the toluene, while a concentrated sodium thiosulfate solution was introduced into the reactor at the beginning of the experiment. The free iodine was extracted from the continuous phase to the sodium thiosulfate-containing drops, the number of which was continuously increasing by coalescence and redispersion. The progress of the extraction process was followed by withdrawing samples of the continuous phase and analyzing the iodine content by light absorption. When M is the number of drops which contain thiosulfate, N the total number of drops,... 

Repeated surgical skin antisepsis and hand washing did not increase serum iodine concentrations, but produced a small increase in iodine content in the 24-hour urine (4). 

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