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Updated: Feb 18, 2026
13:21
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
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Bimetallic lanthanide complexes that display a ratiometric response to oxygen concentrations
Thomas Just Sørensen1,2, Alan M Kenwright3, Stephen Faulkner1
1Chemistry Research Laboratory , University of Oxford , 12 Mansfield Road , Oxford OX1 3TA , UK .
Chemical Science
|November 17, 2017
Summary
New hetero-bimetallic lanthanide complexes with terbium and europium were synthesized. One complex shows terbium emission sensitive to oxygen, while europium emission is stable.
Area of Science:
- Coordination Chemistry
- Materials Science
- Photophysics
Background:
- Lanthanide complexes are crucial for luminescence applications.
- Developing hetero-bimetallic systems offers unique photophysical properties.
- Ugi multi-component reactions provide efficient synthetic routes.
Purpose of the Study:
- To synthesize novel hetero-bimetallic lanthanide complexes.
- To investigate the luminescence properties of terbium and europium ions within these complexes.
- To explore the influence of environmental factors, such as dissolved oxygen, on luminescence.
Main Methods:
- Synthesis of kinetically stable lanthanide precursors.
- Coupling of precursors using Ugi multi-component reaction methodology.
- Incorporation of a naphthyl chromophore for light harvesting.
- Spectroscopic analysis of luminescence properties in solution.
Main Results:
- Successfully prepared two hetero-bimetallic lanthanide complexes containing terbium and europium.
- Both complexes demonstrated luminescence originating from both terbium and europium ions.
- Terbium-centered emission intensity was found to vary with dissolved oxygen concentration.
- Europium emission intensity remained stable in one of the synthesized complexes.
Conclusions:
- The Ugi methodology is effective for creating complex hetero-bimetallic lanthanide structures.
- The synthesized complexes exhibit dual lanthanide luminescence.
- The oxygen sensitivity of terbium emission suggests potential for sensing applications.
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