Chelation therapy for metal intoxication: comments from a thermodynamic viewpoint.
Valeria Marina Nurchi1, Miriam Crespo Alonso, Leonardo Toso
1Dipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Cittadella Universitaria, 09042 Monserrato-Cagliari, Italy.
Mini Reviews in Medicinal Chemistry
|July 31, 2013
Summary
Chelation therapy uses chelating agents to treat metal intoxication. This study evaluates chelator stability and identifies optimal agents for specific toxic metals based on pMe values.
Area of Science:
- Toxicology
- Medicinal Chemistry
- Biochemistry
Background:
- Metal intoxication poses significant health risks.
- Chelation therapy is a primary clinical treatment for metal toxicity.
- Existing chelating agents have limitations and incomplete equilibrium data.
Purpose of the Study:
- To outline the causes of metal toxicity.
- To define the chemical and biomedical requirements for chelating agents.
- To evaluate the stability of various chelators and identify optimal agents for toxic metals.
Main Methods:
- Review of principal causes of metal toxicity.
- Analysis of chemical and biomedical requisites for chelating agents.
- Evaluation of chelator stability constants and pMe values using databases.
- Examination of competition between endogenous and toxic metal ions.
Main Results:
- Chelating agents fall into categories: mercapto, oxygen, polyaminocarboxylic acids, and dithiocarbamates.
- Less than 50% of chelators in use have studied complex formation equilibria.
- Ligands with the best pMe values were selected for each toxic metal.
- The study provides insight into achievable pMe values and suitable chelators.
Conclusions:
- Stability constants are crucial for evaluating chelating agent efficacy.
- Optimal chelators for specific toxic metals can be identified using pMe values.
- Further research is needed to consider biomedical requisites alongside stability for chelator selection.
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