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Updated: Aug 16, 2025
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
Structural Features of Eu3+ and Tb3+-Bipyridinedicarboxamide Complexes
Anna S Miroshnichenko1,2, Konstantin V Deriabin1, Artem A Rashevskii1
1Institute of Chemistry, St. Petersburg University, 7/9 Universitetskaya Emb., St. Petersburg 199034, Russia.
Abstract:
Photoluminescent lanthanide complexes of Eu3+ and Tb3+ as central atoms and N,N-diisopropyl-[2,2'-bipyridine]-6,6'-dicarboxamide as ligand were synthesized. The structure of these complexes was established by single-crystal X-ray diffraction, mass spectrometry, 1H and 13C nuclear magnetic resonance, ultraviolet-visible, infrared spectroscopy, and thermogravimetry. Bipyridinic ligands provide formation of coordinatively saturated complexes of lanthanide ions and strong photoluminescence (PL). The Eu3+- and Tb3+-complexes exhibit PL emission in the red and green regions observed at a 340 nm excitation. The quantum yield for the complexes was revealed to be 36.5 and 12.6% for Tb3+- and Eu3+-complexes, respectively. These lanthanide compounds could be employed as photoluminescent solid-state compounds and as emitting fillers in polymer (for example, polyethylene glycol) photoluminescent materials.
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