Iodine

About: Iodine is a research topic. Over the lifetime, 8936 publications have been published within this topic receiving 139981 citations. The topic is also known as: I & element 53.

Germicidal iodine compositions with enhanced iodine stability

Abstract: New and improved germicidal iodine compositions are provided in which iodine levels, in the presence of organic adjuvants containing at least carbon, hydrogen and oxygen atoms, are maintained for extended periods of time in the presence of iodide, through the addition of iodate and control of pH within the range of pH 5-7.

Iodine speciation in rain, snow and aerosols

Abstract: Iodine oxides, such as iodate, should be the only thermodynamically stable sink species for iodine in the tro- posphere. However, field observations have increasingly found very little iodate and significant amounts of iodide and soluble organically bound iodine (SOI) in precipitation and aerosols. The aim of this study was to investigate io- dine speciation, including the organic fraction, in rain, snow, and aerosols in an attempt to further clarify aqueous phase iodine chemistry. Diurnal aerosol samples were taken with a 5 stage cascade impactor and a virtual impactor (PM2.5) from the Mace Head research station, Ireland, during sum- mer 2006. Rain was collected from Australia, New Zealand, Patagonia, Germany, Ireland, and Switzerland and snow was obtained from Greenland, Germany, Switzerland, and New Zealand. Aerosols were extracted from the filters with water and all samples were analysed for total soluble iodine (TSI) by inductively coupled plasma mass spectrometry (ICP-MS) and iodine speciation was determined by coupling an ion chromatography unit to the ICP-MS. The median concentra- tion of TSI in aerosols from Mace Head was 222 pmol m 3 (summed over all impactor stages) of which the majority was associated with the SOI fraction (median day: 90±4%, night: 94±2% of total iodine). Iodide exhibited higher concen- trations than iodate (median 6% vs. 1.2% of total iodine), and displayed significant enrichment during the day com- pared to the night. Interestingly, up to 5 additional, presum- ably anionic iodo-organic peaks were observed in all IC-ICP- MS chromatograms, composing up to 15% of the TSI. Sol- uble organically bound iodine was also the dominant frac- tion in all rain and snow samples, with lesser amounts of iodide and iodate (iodate was particularly low in snow). Two of the same unidentified peaks found in aerosols were also observed in precipitation from both Southern and Northern Hemispheres. This suggests that these species are transferred from the aerosols into precipitation and that they have ei- ther a relatively long lifetime or are rapidly recycled. It is thought that SOI is formed by reactions between HOI or I2 and organic matter derived from the ocean surface layer. SOI may then photolytically decompose to yield iodide and the unidentified species. The data in this study show that io- dine oxides are the least abundant species in rain, snow, and aerosols and therefore considerably more effort is required on aqueous phase iodine chemistry for a holistic understand- ing of the iodine cycle.

Effects of Transforming Growth Factor-β on Deoxyribonucleic Acid Synthesis and Iodine Metabolism in Porcine Thyroid Cells in Culture*

Abstract: The effect of transforming growth factor (TGF)-β on DNA synthesis and iodine metabolism was studied in cultured porcine thyroid cells. TGF-β dose-dependently inhibited DNA synthesis stimulated by both insulin-like growth factor I and epidermal growth factor but did not affect the number or affinity of receptors for the two growth factors, suggesting that TGF-β inhibits postreceptor events responsible for initiation of DNA synthesis. TGF-β was a potent inhibitor of iodine metabolism. When porcine thyroid cells were cultured with TSH for 3 days in the presence of TGF-β, TSH-induced iodide uptake and organification were reduced at rates that were dependent on the TGF-0 concentrations. The inhibition was detectable at TGF-β concentrations as low as 50 pg/ml, and complete suppression was seen at 1 ng/ml. Only 6 h of exposure to TGF-β resulted in a significant inhibition of TSH-induced iodine metabolism. Treatment of thyroid cells with TGF-β for 3 days did not reduce cAMP production stimulated by TSH. Moreover,...