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Tuning aminopolycarboxylate chelators for efficient complexation of trivalent actinides.

ABSTRACT: The complexation of trivalent lanthanides and minor actinides (Am³⁺, Cm³⁺, and Cf³⁺) by the acyclic aminopolycarboxylate chelators 6,6'-((ethane-1,2-diylbis-((carboxymethyl)azanediyl))bis-(methylene))dipicolinic acid (H₄octapa) and 6,6'-((((4-(1-(2-(2-(2-hydroxyethoxy)ethoxy)ethyl)-1H-1,2,3-triazol-4-yl)pyridine-2,6-diyl)bis-(methylene))bis-((carboxymethyl)azanediyl))bis-(methylene)) dipicolinic acid (H₄pypa-peg) were studied using potentiometry, spectroscopy, competitive complexation liquid-liquid extraction, and ab initio molecular dynamics simulations. Two studied reagents are strong multidentate chelators, well-suited for applications seeking radiometal coordination for in-vivo delivery and f-element isolation. The previously reported H₄octapa forms a compact coordination packet, while H₄pypa-peg is less sterically constrained due to the presence of central pyridine ring. The solubility of H₄octapa is limited in a non-complexing high ionic strength perchlorate media. However, the introduction of a polyethylene glycol group in H₄pypa-peg increased the solubility without influencing its ability to complex the lanthanides and minor actinides in solution.

SUBMITTER: Pilgrim CD

PROVIDER: S-EPMC10587169 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Tuning aminopolycarboxylate chelators for efficient complexation of trivalent actinides.

Pilgrim Corey D CD Grimes Travis S TS Smith Clayn C Heathman Colt R CR Mathew Jopaul J Jansone-Popova Santa S Roy Santanu S Ray Debmalya D Bryantsev Vyacheslav S VS Zalupski Peter R PR

Scientific reports 20231019 1

The complexation of trivalent lanthanides and minor actinides (Am3+, Cm3+, and Cf3+) by the acyclic aminopolycarboxylate chelators 6,6'-((ethane-1,2-diylbis-((carboxymethyl)azanediyl))bis-(methylene))dipicolinic acid (H4octapa) and 6,6'-((((4-(1-(2-(2-(2-hydroxyethoxy)ethoxy)ethyl)-1H-1,2,3-triazol-4-yl)pyridine-2,6-diyl)bis-(methylene))bis-((carboxymethyl)azanediyl))bis-(methylene)) dipicolinic acid (H4pypa-peg) were studied using potentiom ...[more]

PMID: 37857726

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Tuning aminopolycarboxylate chelators for efficient complexation of trivalent actinides.

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Tuning aminopolycarboxylate chelators for efficient complexation of trivalent actinides.

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