Iodination of Molecules with Low MW

Iodized molecules with low MW serve as ligands in binding assays, for the indirect iodination of proteins, or as photoaffinity ligands. Typically these are phenol compounds. 

In the iodination of molecules with low MW, Na I usually serves as the source of and chloramine T as the oxidizer (molar ration of the three reactants about 1 1 1). A slightly basic pH of the reaction mixture favors the monoiodination. With compounds that are sensitive to water (e.g., N-succinimidyl derivatives), the iodination reaction is carried out in organic solvents (e.g., acetone, acetonitrile). The iodination efficiency depends on the solvent being used. HPLC or thin-layer chromatography separates free iodine, iodized molecule, and noniodized molecule. 

Kometani, T., et al. (1985a). Iodination of Phenols Using Chloramine-T and Sodium Iodide, Tetrahedron Letters 26 2043-2046. 

Masson, J., and Labia, R. (1983). Synthesis of a l-radiolabelled Penicillin for Penicillin Binding Proteins, Anal. Biochem. 128 164—168. 

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