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Updated: Mar 15, 2026

An Aptamer-based Sensor for Unchelated GadoliniumIII
Published on: January 9, 2017
High kinetic inertness of a bis-hydrated Gd-complex with a constrained AAZTA-like ligand
Adrienn Vágner1, Eliana Gianolio, Silvio Aime
1Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4032, Debrecen, Egyetem tér 1, Hungary.
Abstract:
Kinetic inertness is a key property for a Gd-based contrast agent. The Gd(III) complex of a cyclohexyl-fused AAZTA derivative shows the highest kinetic inertness for non-macrocyclic bis hydrated (q = 2) Gd(III)-complexes with a dissociation half-life of 91 years under physiological conditions, very close to that of macrocyclic clinically approved contrast agents. It also shows optimal relaxometric performance (r1 = 8.3 mM(-1) s(-1) at 20 MHz and 25 °C) due to the presence of two inner sphere water molecules in fast exchange with bulk water and not displaced by endogenous anions.
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