Iodine immobilization

Nakazawa, T., Kato, H., Okada, K., Ueta, S. Mihara, M. 2001. Iodine immobilization by Sodalite waste form. Materials Research Society Symposium Proceedings, 663, 51-58. 

Iodine Immobilization Three different waste forms were proposed for 1-129 in the 1980s (Trevorrow et al., 1983). Two of these utilized zeolites for capture. Two of the final waste forms incorporated cement into the system for immobilization and the third consisted of pellets. As Trevorrow et al. (1983) stated in their report "The very small release limit for 1-129 specified by 40 CFR 190 (Table 14.10) makes extreme demands on technologies of collection and retention for this nuclide. Furthermore, the assessment of whether the technologies will comply with this limit is affected by uncertainties such as the distribution of iodine in the plant or the efficiency of the technology for collecting 1-129 from gas streams" (Me Kay, 1980). 

The Turing mechanism requires that the diffusion coefficients of the activator and inlribitor be sufficiently different but the diffusion coefficients of small molecules in solution differ very little. The chemical Turing patterns seen in the CIMA reaction used starch as an indicator for iodine. The starch indicator complexes with iodide which is the activator species in the reaction. As a result, the complexing reaction with the immobilized starch molecules must be accounted for in the mechanism and leads to the possibility of Turing pattern fonnation even if the diffusion coefficients of the activator and inlribitor species are the same 62. 

TES-32 is the most abundant single protein product secreted by the parasite. It is also heavily labelled by surface iodination of live larvae (Maizels et al., 1984, 1987), and is known by monoclonal antibody reactivity to be expressed in the cuticular matrix of the larval parasite (Page et al, 1992a). TES-32 was cloned by matching peptide sequence derived from gel-purified protein to an expressed sequence tag (EST) dataset of randomly selected clones from a larval cDNA library (Loukas et al., 1999). Because of the high level of expression of TES-32 mRNA, clones encoding this protein were repeatedly sequenced and deposited in the dataset (Tetteh et al., 1999). Full sequence determination showed a major domain with similarity to mammalian C-type (calcium-dependent) lectins (C-TLs), together with shorter N-terminal tracts rich in cysteine and threonine residues. Native TES-32 was then shown to bind to immobilized monosaccharides in a calcium-dependent manner (Loukas et al., 1999). 

Figure 12.6 The immobilized glucose oxidase/lactoperoxidase system radioiodinates proteins through the intermediate formation of hydrogen peroxide from the oxidation of glucose. H2O2 then reacts with iodide anions to form reactive iodine (I2). This efficiently drives the formation of the highly reactive H2OI+ species that is capable of iodinating tyrosine or histidine residues (see Figure 12.2).

Tsang SC, Guo ZJ, Chen YK, Green MLH, Hill HAO, Hambley TW, Sadler PJ (1997) Immobilization of platinated and iodinated oligonucleotides on carbon nanotubes. Angew. Chem. Int. Ed. Engl. 36 2198-2200. 

Bahrami K, Khodaei MM, Farrokhi A (2009) Highly efficient solvent-free synthesis of dihydropyrimidinones catalyzed by zinc oxide. Synth Commun 39 1801-1808 74. Gross GA, Wurziger H, Schober A (2006) Solid-phase synthesis of 4,6-diaryl-3,4-dihydro-pyrimidine-2(lH)-one-5-carboxylic acid amide derivatives a Biginelli three-component-condensation protocol based on immobilized beta-ketoamides. J Comb Chem 8 153-155 Desai B, Dallinger D, Kappe CO (2006) Microwave-assisted solution phase synthesis of dihydropyrimidine C5 amides and esters. Tetrahedron 62 4651 664 Kumar A, Maurya RA (2007) An efficient bakers yeast catalyzed synthesis of 3,4-dihydro-pyrimidin-2-(lH)-ones. Tetrahedron Lett 48 4569-4571 77. Zalavadiya P, Tala S, Akbari J, Joshi H (2009) Multi-component synthesis of dihydropyrimidines by iodine catalyst at ambient temperature and in-vitro anti mycobacterial activity. Arch Pharm 342 469-475... 

Polystyrene-bound alkenes react with alcohols or amines in the presence of mercury(II) trifluoroacetate to yield 2-alkoxy- or 2-aminoethylmercury compounds [30]. The C-Hg bond can be reduced to a C-H bond by treatment with LiBH4, or converted into a C-I bond by treatment with iodine [30]. Organomercury compounds have been immobilized with polystyrene-bound carboxylates [31]. The resulting product was used as starting material for the preparation of radiolabelled 6-iodo DOPA (Figure 4.4). 

Figure 265 IODO-BEADS contains immobilized Chloramine-T functional groups that can react with radioactive iodide in aqueous solution to form a highly reactive intermediate. The active species may be an iodosulfonamide derivative, which then can iodinate tyrosine or histidine residues in proteins.

If the waste is isolated in a geologic repository, the iodine form should be stable to at least 100°C and possibly at 250°C depending on the repository site. If the waste form satisfies the thermal stability requirement, the most likely release mechanism then becomes leaching in the event that groundwater contacts the immobilization form. Allard et al. (11) report log Kd values for silicate minerals ranging from -0.5 to -3.5. Fried et al. (12) found little retention of iodine (as iodide or iodate) by Los Alamos Tuff. Thus, once the Iodine has been removed by leaching, it will potentially move at the same velocity as the groundwater. 

A known amount of [125I]dioxin is added to a series of antibody-containing tubes. An increasing amount of unlabeled dioxin is added to each tube. The solutions are incubated, during which time the iodinated dioxin and the noniodinated dioxin will compete for binding with the immobilized antibodies. 

The iodination with lactoperoxidase is also very gentle and very often used Because the application of an enzyme for oxidation is more expensive than the use of common oxidation reagents, procedures involving immobilized lactoperoxidase have been worked out 21.22.26)... 

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