Datensatz

Zusammenfassung

Zinc ions play an important role in numerous crucial biological processes in the human body. The ability to image the function of Zn 2+ would be a significant asset to biomedical research for monitoring various physiopathologies dependent on its fate. To this end, we developed a novel Gd 3+ chelate that can selectively recognize Zn 2+ over other abundant endogenous metal ions and alter its paramagnetic properties. More specifically, this lanthanide chelate displayed an extraordinary increase in longitudinal relaxivity ( r 1 ) of over 400% upon interaction with Zn 2+ at 7 T and 25 °C, which is the greatest r 1 enhancement observed for any of the metal ion-responsive Gd-based complexes at high magnetic field. A "turn-on" mechanism responsible for these massive changes was confirmed through NMR and luminescence lifetime studies on a 13 C-labeled Eu 3+ analogue. This molecular platform represents a new momentum in developing highly suitable magnetic resonance imaging contrast agents for functional molecular imaging studies of Zn 2+ .