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Coordination studies of Al-EDTA in aqueous solution
Orkid Coskuner1, Emily A A Jarvis
1Physical and Chemical Properties Division, National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 8380, Gaithersburg, Maryland 20889, USA. orkid.coskuner@nist.gov
The Journal of Physical Chemistry. A
|February 26, 2008
Summary
Aluminum toxicity depends on its complexation with ligands like aluminum ethylenediaminetetraacetate (AlEDTA-). This study predicts AlEDTA- favors octahedral coordination in aqueous solution, aligning with experimental data.
Area of Science:
- Environmental Chemistry
- Computational Chemistry
- Biochemistry
Background:
- Aluminum toxicity is influenced by its complexation with organic ligands.
- The coordination structure of aluminum ethylenediaminetetraacetate (AlEDTA-) in aqueous solution remains debated, impacting bioactivity interpretations.
Purpose of the Study:
- To predict the coordination of aluminum in aqueous AlEDTA-.
- To resolve the debate on AlEDTA- structure in solution and its relation to crystalline forms.
Main Methods:
- Ab initio calculations.
- Car-Parrinello molecular dynamics simulations.
Main Results:
- AlEDTA- favors aluminum in octahedral coordination in aqueous solution.
- Predicted structures align with recent X-ray measurements, supporting AlEDTA-'s chelating properties.
Conclusions:
- The study clarifies the aqueous coordination of AlEDTA-.
- Results support the strong chelating nature of AlEDTA- and its structural similarity in crystalline and solution phases.
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