Mixed Complexes of Copper(II) Nitrilotriacetate with Triglycine in Solution

Potentiometric, calorimetric, and spectrophotometric studies on mixed-ligand complexes of copper(II) nitrilotriacetate (Nta) and glycinate (Gly) with simple tripeptide GlyGlyGly (GGG) have been carried out in aqueous solution at 298.15 K and the ionic strength of I = 0.5 (KNO 3 ). The thermodynamic parameters of formation of various mixed complexes have been determined. The probable coordination modes of the complexone and peptide molecule in the mixed-ligand complexes were discussed.