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Updated: Oct 18, 2025
13:21
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
15.1K
Influence of Divalent Cations in the Protein Crystallization Process Assisted by Lanthanide-Based Additives
Amandine Roux1,2, Romain Talon3, Zaynab Alsalman3
1Laboratoire de Chimie, ENS de Lyon, CNRS, UMR 5182, Université Lyon, Lyon F-69342, France.
Inorganic Chemistry
|October 1, 2021
Summary
Lanthanide complexes are useful in biocrystallography. This study compares [Eu(DPA)3]3- and Tb-Xo4, finding Tb-Xo4 more stable and suitable for high-throughput screening, forming complex adducts with proteins.
Area of Science:
- Biochemistry
- Crystallography
- Supramolecular Chemistry
Background:
- Lanthanide complexes serve as valuable auxiliaries in biocrystallography.
- Evaluating the impact of crystallization kit composition on lanthanide additive efficiency is crucial for high-throughput screening.
Purpose of the Study:
- To systematically analyze the influence of commercial crystallization kit composition on the efficiency of [Eu(DPA)3]3- and Tb-Xo4 lanthanide additives.
- To compare the stability and suitability of these two lanthanide complexes for biocrystallography applications.
Main Methods:
- Systematic analysis of commercial crystallization kit components.
- Investigation of lanthanide complex stability and solubility in various media.
- X-ray crystallography to determine the structures of lanthanide complexes and adducts.
Main Results:
- [Eu(DPA)3]3- exhibits lower chemical stability and a high rate of false positives, limiting its utility in automated platforms.
- Tb-Xo4 demonstrates excellent solubility, stability with alkaline-earth cations, and slow decomposition with transition metals.
- Novel crystal structures of lanthanide complexes and multicomponent adducts formed within protein binding sites were determined.
Conclusions:
- Tb-Xo4 is a more robust and reliable lanthanide additive for biocrystallography compared to [Eu(DPA)3]3-.
- The study highlights the complex supramolecular interactions occurring at protein surfaces, involving lanthanide complexes and crystallization additives.
- Findings provide insights into optimizing lanthanide-assisted crystallization strategies for protein structure determination.
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