Iodic Research Articles

Initial inhomogeneity-induced crazy-clock behavior in the iodate-arsenous acid reaction in a buffered medium under stirred batch conditions.

It is unambiguously demonstrated that in the case of an autocatalytic reaction, initial inhomogeneities induced by the imperfectly mixed part of the overall volume may result in a serious irreproducibility of the individual kinetic runs. A statistically meaningful number of repetitions, however, gives rise to a reproducible cumulative probability distribution curve often referred to as a support of the stochastic feature. The iodate-arsenous acid reaction being autocatalytic with respect to both iodide and hydrogen ions displays clock behavior. However, the time lag necessary for the appearance of iodine, even in buffered solution, varies in an apparently random manner. Careful analysis of the variation of the different parameters like stirring rate, overall volume, geometry of the reactor and the way of mixing the reactants led us to conclude that the fate of the individual samples is determined at the initial stage when the reacting system is per se inhomogeneous. The place, the size of the so-called ignition volume, where the reacting system is imperfectly stirred, as well as the residence time spent there by the imperfectly mixed reactants all seem to depend on external factors.

Four brilliant students of Henri Sainte-Claire Deville 4. Alfred Ditte

Alfred Ditte (1843–1908), a student of Henri Sainte-Claire Deville, carried on a large number of important researches in the areas of mineralogy, chemistry, and thermodynamics, in particular, vanadium and its compounds, properties of aluminum, alumina, and aluminates, the Leclanché cell, dissociation mechanism, and iodic acid and iodates.

Ln(IO3)3 (Ln = Ce, Nd, Eu, Gd, Er, Yb) polycrystals as novel photocatalysts for efficient decontamination under ultraviolet light irradiation.

Ln(IO3)3 (Ln = Ce, Nd, Eu, Gd, Er, Yb) polycrystals were hydrothermally synthesized using lanthanide nitrate or lanthanide oxide and iodic acid as precursors. X-ray diffraction was used to characterize the crystal structures of the Ln(IO3)3 products. Scanning electron microscopy was carried out to observe the microscopic morphologies. The lattice spacings were studied by high-resolution transmission electron microscopy and selected area electron diffraction. We evaluated the photocatalytic efficiency by decomposing methyl orange dye under ultraviolet light irradiation, and the Ln(IO3)3 products show excellent photocatalytic properties. To rule out the effect of photosensitization, 2,4-dichlorophenol was also photodegraded. As one of the key factors of photocatalysis, ultraviolet-visible diffuse reflectance spectra of the Ln(IO3)3 samples were also studied, and all products have strong absorption in the ultraviolet region.

The experimental study of ^131I labeling prostate stem cell antigen monoclonal antibody in the treat-ment of nude mice bearing orthotopic implantation of prostate carcinomar

Objective To study the distribution, radioimmunoimaging and anti-tumor effect of ^131I labeling prostate stem cell antigen monoclonal antibody （^131I-PSCA-McAb） in nude mice bearing orthotopic implantation of prostate carcinoma. Methods Thirty-six male nude mice were randomly divided into 2 groups： LNCap cell group （androgen dependent prostate cancer） and PC3 cell group （androgen independent prostate cancer）. Each group were then subdivided into 3 subgroups： experimental group （were intrave noused 1311-PSCA-McAb 200 μg）, monoclonal control group （were intravenoused PSCA-McAb 200 μg）, iodic control group （ were intravenoused 1311 200 μg）. Continuous images of nude mice bearing LNCap cell and PC3 cell were carried out respectively at 1, 4, 8, 12 and 24 h after drugs injection. Transplantation tumor images were then observed and the radioactivity ratio of tumor/non-tumor （T/NT） was calculated. 48 h later, nude mice were sacrificed and the apoptosis of tumor tissues were measured by TdT-mediated dUTP nick end labeling （TUNEL）. Results The models of nude mice bearing orthotopic implantation of prostate carcinoma were successfully established. The peak uptake of ^131I_PSCA.McAb in orthotopic tumor of prostate carcinoma was at 8h after injection with a T/NT ratio of 4.37 ± 0. 76 （LNCap cell group） and 4. 21±0. 71 （PC3 cell group） respectively. The number of TUNEL positive cells in experimental group was larger than that of the two other control groups. Conclusion ^131 I-PSCA-McAb could effectively target PSCA and inhibit the growth of tumor, therefore was a promising radioimmunotherapy radiophamaceutical for prostate carcinoma. Key words: Models of orthotopic implantation of prostate cancer; ^131I labeling prostate stem cellantigen monoclonal antibody; Cell apoptosis; Radioimmunotherapy

Inhibitive effects of 131I labeling prostate stem cell antigen monoclonal antibody on prostate carcinoma cell line LNCap and PC3

Objective To investigate the inhibitive effects of 131Ⅰ labeling prostate stem cell antigen monoclonal antibody (131 Ⅰ-PSCA-McAb) on prostate carcinoma cell line LNCap and PC3 in vitro.Methods Prostate carcinoma LNCap cells and PC3 cells were cultured in vitro,and each cell line was divided into 4 groups:experimental group (adding 131Ⅰ-PSCA-McAb 2 g/L),monoclonal control group (adding PSCA-McAb 2 g/L),iodic control group (adding 131I 2 g/L),blank control group (adding saline solution 2 g/L).Cell inhibition of proliferation in each group was tested by methyl thiazol tetrazolium (MTF) assay; tumor apoptosis in each group was measured by flow cytometry; and invasiveness of cells was detected by Transwell invasion test.Results The inhibitory rates of LNCap experimental group and PC3 exerimental group reached (83.67 ± 2.52)％ and (80.33 ± 4.51)％,which obviously higher than monoclonal control groups [(73.33 ± 3.51)％ and (66.67 ± 5.03)％,P＜ 0.05] and iodic control groups [(53.33 ±4.51) ％ and (56.33 ± 2.52) ％,P ＜ 0.05].The apoptosis rates of LNCap experimental group and PC3 exerimental group reached (50.24 ±5.52)％ and (54.71 ±5.84)％ respectively,which obviously higher than monoclonal control groups [(42.23 ± 4.87)％ and (45.61 ± 5.60)％,P ＜0.05],iodic control groups [(26.75 ± 3.43) ％ and (22.26 ± 3.71) ％,P ＜ 0.05] and blank control groups [(14.18 ± 3.97) ％ and (15.14 ± 3.28) ％,P ＜ 0.05].The number of cells invading the membrane in LNCap experimental group and PC3 exerimental group was 33.34 ± 5.82 and 34.91 ± 6.10 respectively,which obviously less than monoclonal control groups (89.15 ± 7.96 and 92.04 ± 8.44,P ＜0.05),iodic control groups (97.83 ± 9.21 and 88.30 ± 8.12,P＜ 0.05) and blank control groups (119.04 ± 10.57 and 115.56 ± 11.08,P ＜ 0.05).Conclusion 131 Ⅰ-PSCA-mAb could effectively inhibit the growth and invasion ability of prostate carcinoma cell line LNCap and PC3,promote the apoptosis,and has the potential to become a new targeted therapy drug for the treatment of prostate carcinoma.131 Ⅰ-PSCA-McAb could effectively target PSCA and inhibit the growth of tumor,therefore was a promising radioimmunotherapy radiophamaceutical for prostate cancer. Key words: 131Ⅰ labeling prostate stem cell antigen monoclonal antibody; Cell proliferation; Cell apoptosis; Cell invasion; Radioimmunotherapy

Oxyhalogen–Sulfur Chemistry: Kinetics and Mechanism of Oxidation of N-Acetyl-ʟ-methionine by Aqueous Iodine and Acidified Iodate

The use of N-acetyl-l-methionine (NAM) as a bio-available source for methionine supplementation as well as its ability to reduce the toxicity of acetaminophen poisoning has been reported. Its interaction with the complex physiological matrix, however, has not been thoroughly investigated. This manuscript reports on the kinetics and mechanism of oxidation of NAM by acidic iodate and aqueous iodine. Oxidation of NAM proceeds by a two electron transfer process resulting in formation of a sole product: N-acetyl-l-methionine sulfoxide (NAMS=O). Data from electrospray ionization mass spectrometry confirmed the product of oxidation as NAMS=O. The stoichiometry of the reaction was deduced to be IO3– + 3NAM → I– + 3NAMS=O. In excess iodate, the stoichiometry was deduced to be 2IO3– + 5NAM + 2H+ → I2 + 5NAMS=O + H2O. The reaction between aqueous iodine and NAM gave a 1 : 1 stoichiometric ratio: NAM + I2 + H2O → NAMS=O + 2I– + H+. This reaction was relatively rapid when compared with that between NAM and iodate. It did, however, exhibit some auto-inhibitory effects through the formation of triiodide (I3–) which is a relatively inert electrophile when compared with aqueous iodine. A simple mechanism containing 11 reactions gave a reasonably good fit to the experimental data.

Cytodiagnosis of extragonadal pure yolk sac tumor of sacrococcygeal region

Yolk sac tumors (YST) are rare in extragonadal location. Cytologic diagnosis of YST in such instances may be a challenge to the pathologist. We studied Fine needle Aspiration (FNA) material from a sacrococcygeal mass in a 18-month-old female child presenting with a progressively increasing sacrococcygeal mass. Cytologic features include large pleomorphic balls of tumor cells with high nuclear to cytoplasmic ratios, papillary or micro-glandular pattern of growth, cytoplasmic and intra-nuclear vacuoles, and prominent nucleoli. Per Iodic Acid Schiff (PAS) positive intra-cytoplasmic as well as extracellular hyaline globules were also seen. The subsequent biopsy was consistent with the FNA diagnosis, and immuno-histochemically, the tumor cells were positive for Alpha Feto Protein (AFP) supporting the diagnosis.

Oxidative Breakdown of Iodoalkanes to Catalytically Active Iodine Species: A Case Study in the α-Tosyloxylation of Ketones

Catalysis of the oxidative processes by iodoarenes has become a promising direction in synthesis. The mechanism, involving the well-known isolable hypervalent iodine species, is generally limited to aromatic iodides, since the corresponding aliphatic species are normally highly unstable. Nevertheless, in this work catalytic amount of several primary, secondary or tertiary iodoalkanes were found to promotes the α-tosyloxylation of a range of ketones with RSO3H, including aliphatic sulfonates. The process, was found to proceed through the oxidative breakdown of the iodoalkane to an inorganic catalytic species (likely IO− or IO2−), thus falling within the previously described catalysis using molecular iodine or inorganic iodides. The catalyst eventually becomes deactivated through the precipitation of an iodine overoxidation product, the structure of which was solved ab initio from the powder diffraction data as a hitherto unreported phase of the iodic acid (HIO3).

Synthesis, Characterization and Evaluation of Property Profile of Hybrid Ion- Exchanger

Gum tragancanth based organic-inorganic hybrid ion exchanger has been synthesized using a mixture of sodium tungstate, orthophosphoric acid and potassium iodate. The different reaction conditions like reaction temperature, reaction time, pH of reaction medium, solvent volume, monomer concentration and initiator concentration were optimized in order to get the semi-IPN Gt-cl-poly (AA). Onto semi IPN, methylmethacrylate was incorporated using lipase-gluteraldehyde as the initiator-crosslinker system. The IPN finally was converted into ion-exchanger and was studied for its different physico-chemical properties. Ion exchange capacity was studied for Na+ and effect of different temperatures on ion exchange capacity was evaluated. Characterization was done using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and EDS techniques.

2-Methoxyethanol: A remarkably efficient and alternative reaction medium for iodination of reactive aromatics using iodine and iodic acid

Remarkably effective iodination of reactive aromatics carried out using iodine and iodic acid in 2-methoxyethanol as an efficient and alternative reaction medium. The comparison has been made by carrying out iodination reaction in acetic acid and ethanol. The 2-methoxyethanol is found to be excellent reaction solvent in terms of clean reaction conditions, short reaction time giving quantitative yields of product and no need of further purification .

Selective iodination of 2-acetyl-1-naphthol using iodine and iodic acid under solvent-free grinding technique

Selective electrophilic iodination of 2-acetyl-1-naphthol was achieved using iodine and iodic acid in combination with grinding at room temperature under solvent-free conditions to yield 1-(1-hydroxy-4-iodo-naphthalen-2-yl)-ethanone. Grinding mode of reactions has not only of interest from economical point of view, in many cases they also offer considerable advantages in terms of yield, mild reaction conditions, selectivity and simplicity of reaction procedure.

Accounting for Changes in Particle Charge, Dry Mass and Composition Occurring During Studies of Single Levitated Particles

The most used instrument in single particle hygroscopic analysis over the past thirty years has been the electrodynamic balance (EDB). Two general assumptions are made in hygroscopic studies involving the EDB. First, it is assumed that the net charge on the droplet is invariant over the time scale required to record a hygroscopic growth cycle. Second, it is assumed that the composition of the droplet is constant (aside from the addition and removal of water). In this study, we demonstrate that these assumptions cannot always be made and may indeed prove incorrect. The presence of net charge in the humidified vapor phase reduces the total net charge retained by the droplet over prolonged levitation periods. The gradual reduction in charge limits the reproducibility of hygroscopicity measurements made on repeated RH cycles with a single particle, or prolonged experiments in which the particle is held at a high relative humidity. Further, two contrasting examples of the influence of changes in chemical composition changes are reported. In the first, simple acid-base chemistry in the droplet leads to the irreversible removal of gaseous ammonia from a droplet containing an ammonium salt on a time scale that is shorter than the hygroscopicity measurement. In the second example, the net charge on the droplet (<100 fC) is high enough to drive redox chemistry within the droplet. This is demonstrated by the reduction of iodic acid in a droplet made solely of iodic acid and water to form iodine and an iodate salt.

Glass formation and unusual hygroscopic growth of iodic acid solution droplets with relevance for iodine mediated particle formation in the marine boundary layer

Abstract. Iodine oxide particles are known to nucleate in the marine boundary layer where gas phase molecular iodine and organoiodine species are produced by macroalgae. These ultra-fine particles may then grow through the condensation of other materials to sizes where they may serve as cloud condensation nuclei. There has been some debate over the chemical identity of the initially nucleated particles. In laboratory simulations, hygroscopic measurements have been used to infer that they are composed of insoluble I2O4, while elemental analysis of laboratory generated particles suggests soluble I2O5 or its hydrated form iodic acid, HIO3 (I2O5·H2O). In this paper we explore the response of super-micron sized aqueous iodic acid solution droplets to varying humidity using both Raman microscopy and single particle electrodynamic traps. These measurements reveal that the propensity of an iodic acid solution droplet to crystallise is negligible on drying to ~0% relative humidity (RH). On applying mechanical pressure to these droplets they shatter in a manner consistent with an ultra-viscous liquid or a brittle glass. Water retention in amorphous material at low RH is important for understanding the hygroscopic growth of aerosol particles and uptake of other condensable material. Subsequent water uptake between 10 and 20% RH causes their viscosity to reduce sufficiently that the cracked droplets flow and merge. The persistence of iodic acid solution in an amorphous state, rather than a crystalline state, suggests they will more readily accommodate other condensable material and are therefore more likely to grow to sizes where they may serve as cloud condensation nuclei. On increasing the humidity to ~90% the mass of the droplets only increases by ~20% with a corresponding increase in radius of only 6%, which is remarkably small for a highly soluble material. We suggest that the small growth factor of aqueous iodic acid solution droplets is consistent with the small aerosol growth factors observed in previous experiments.

ChemInform Abstract: Ruthenium(II)‐Catalyzed Synthesis of Hydroxylated Arenes with Ester as an Effective Directing Group.

AbstractK2S2O8, iodic acid or Selectfluor can be used as oxidants to afford ortho‐hydroxylated benzoates selectively.

Effect of Iodic Acid Dopant on the Growth and Structural, Optical, and Electrical Properties of L-Arginine Phosphate Single Crystals

Effect of iodic acid on the growth and properties of L-arginine phosphate (LAP) single crystals has been studied. The presence of iodic acid in the LAP crystals is confirmed by inductively coupled plasma mass spectrometry (ICP-MS) analysis. The unit cell parameters for pure and iodic acid doped LAP crystals have been estimated using powder X-ray diffraction (XRD) analysis. UV-Visible transmittance spectral studies revealed the transmittance percentage and cut-off wavelengths of pure and doped LAP crystals. Powder second harmonic generation measurement has been carried out for the grown LAP crystals. The dielectric behavior of the grown crystals was analyzed for different frequencies at room temperature.

Synthesis, characterization and application of iodine modified titanium dioxide in phototcatalytical reactions under visible light irradiation

Iodine doped titanium dioxide has been successfully prepared by simple hydrolysis of tetrabutyl titanate in the presence of iodic acid. The adopted method allowed for the production of spherical iodine doped titaniun dioxide nanoparticles with varied amount of iodine content. Analysis by X-ray diffraction, Raman, transmission electron microscopy as well as UV–vis DRS revealed that titanium dioxide nanostructures were doped with iodine which existed in two different valence states I5+ and I−. The iodine in the form of I5+ is believed to have doped into the lattice whereas I− was well dispersed on the surface of TiO2 probably as iodine adducts hence rendering it to be highly absorbing in visible light region. The I-TiO2 exhibited improved photocatalytic activity toward degradation of acid orange 7 (AO7), methyl orange (MO) and 2,4-dichlorophenol (2,4-DCP) under visible light over the pristine TiO2 prepared by the same method. High catalytic properties are attributed to iodine doping which led to high specific surface area, absorption in visible region as well as alleviation of charge carrier recombination. The most probable route undertaken in the degradation of AO7 is through indirect oxidation by the hydroxyl radicals.

Removal of Odor Originating from Kitchen Wastewater Treatment Facilities by Activated Carbon Impregnated Iodic Acid

Removal of Odor Originating from Kitchen Wastewater Treatment Facilities by Activated Carbon Impregnated Iodic Acid

Extremely short halogen bond: the nature and energy of iodine–oxygen interactions in crystalline iodic acid

The mechanism of the hypercoordination of the iodine atom and its role in the crystal packing of iodic acid were examined within the topological analysis of the experimental electron density function.

Influence of zirconium doping on the activities of zirconium and iodine co-doped titanium dioxide in the decolorization of methyl orange under visible light irradiation

Zirconium and iodine co-doped titanium dioxide (Zr–I–TiO2) was prepared by the hydrolysis of tetrabutyl titanate, premixed with zirconium nitrate in an iodic acid aqueous solution, followed by calcination in air. The structure and properties of the resultant catalyst powders were characterized by X-ray diffraction, the Brunauer–Emmett–Teller method, X-ray photoelectron spectroscopy, transmission electron microscopy, and UV–vis absorption spectroscopy. The catalytic activity of the catalyst was evaluated by monitoring the photocatalytic decolorization of methyl orange under visible light irradiation. The results showed that the activities of Zr–I–TiO2 catalysts were higher than that of TiO2 doped with iodine alone (I–TiO2), and the optimal doping concentration in the Zr–I–TiO2 calcined at 400°C was determined to be about 0.05 (molar ratio of Zr:Ti). In addition, the photocatalytic activity of Zr–I–TiO2 calcined at 400°C was found to be significantly higher than that calcined at 500 or 600°C. Based on the physico-chemical characterization, we concluded that the role of zirconium on the I–TiO2 surface is to increase the number of reactive sites by generating a small crystal size and large surface area. The inhibition of electron–hole pair recombination, by trapping photo-generated electrons with Zr4+, did not contribute markedly to the improved photocatalytic activity of Zr–I–TiO2.

Incorporation of iodate into uranyl borates and its implication for the immobilization of 129I in nuclear waste repositories

Abstract A series of uranyl borates, UO2B2O4, Na[(UO2)B6O10(OH)]3· 2H2O, and K2[(UO2)2B12O19(OH)4]·0.3H2O, with different topologies have been prepared and tested for the incorporation of iodate, one of the chemical forms that 129I should have in nuclear waste. Laser ablation ICP-MS was used to determine the iodine content in single crystals of the three different uranyl borates. Iodine levels can be greater than 3200 ppm in crystals synthesized in the presence of iodate. The intercalation of iodic acid is one possible mechanism for iodate uptake in these solids.