Thermodynamics of Mixed-Ligand Complexation of Gadolinium Ethylenediaminetetraacetate with Amino Acids in Aqueous Solution

摘要

Mixed-ligand complexation of GdEdta~- with glycinate, L-glutamate, DL-aspartate, iminodiac-etate, and nitrilotriacetate anions in aqueous solutions at 298.15 K and the ionic strength I= 0.5 (KNO3) was studied. The thermodynamic parameters (logK, Δ_rg, Δ_rH, Δ_rS) of these reactions were determined from cal-orimetric and pH-metric data. The most probable way of coordination of the amino acids in the heteroleptic complexes is discussed.