Executive Summary : | The research aims to develop a new strategy for trapping uranyl ion with organoselenium compounds, incorporating organic species bearing heteroatoms as donors. A series of acyclic species bearing phenolic, HC=N, or reduced form (CH2NH) and se heteroatoms will be synthesized as additional donor functionalities. Unique coordination binding sites on selenium-based ligands, such as two ortho-coordinating selenol moieties, phosphate esters of vitamin B6, and selenium macrocycles, will provide selective coordination structures with uranyl ion. The molecular decorporation ligands have been widely researched for decades, offering advantages in metal binding selectivity, toxicity, and oxidative stress alleviation. Multidentate species can provide ideal equatorially binding donor sites to linear uranyl ion, forming mononuclear to a dinuclear structure of predictable geometry. 22- and 24-membered selenium macrocycles containing imine/amine will be used as donor species for efficient binding uranyl ion. The functional activity of uranyl ion will be examined with tridentate or pentadentate type amino donors bearing phenolic, azomethine, and organoselenium coordinating sites with suitable steric and electronic properties. The presence of four amino groups along with selenium donor atoms makes the donor species more basic and may work better for accommodating uranyl ion in its deprotonated state. UV-Vis titration experiments will be conducted to assess the binding properties of these donor species for uranyl ions in solution state, providing useful information regarding uranyl ion speciation or extraction. DNA-binding studies will also be investigated using selective solvents and interpreting spectra over different time spans. |