A comparative research has been developed for acidity and stability constants of M(TTA)1 and M(Asp)2 complexes which have been determined by potentiometric pH titration. Depending on metal ion–binding properties, vital differences in building complex were observed. The present study shows that in M(TTA) complexes, metal ions are coordinated to the carboxyl groups, but in M(Asp) some metal ions are able to build macrochelate over amine group. Hence, the following intermolecular and as a result independent concentration equilibrium between an open–isomer M(Asp)op and a closed–isomer M(Asp)cl, has to be considered cl op. The amounts are reported. The results mentioned above demonstrate that for some M(Asp) complexes the stability constants is also largely determined by the affinity of metal ions for amine group. This leads to a kind of selectivity of metal ions and transfer them via building complexes with the aspartate. The result of this effect is a higher dosage-absorption of minerals in body. Based on the sort of metal ions, the drug-therapy can be different. For heavy metal ions this building complex helps the absorption and filtration of the blood plasma, and consequently the excursion of heavy metal ions takes place. This is an important method in microdialysis. Other metal ions such as the complexes can be considered as mineral carriers. These complexes in certain conditions (PH–range) can release the minerals in body.
IUPAC-IUBMB Joint Commission on Biochemical Nomenclature. Nomenclature and Symbolism for Amino Acids and Peptides, Recommendations on Organic & Biochemical Nomenclature, Symbols & Terminology etc. Retrieved on 2007-05-17.