Solution equilibria of binary and ternary systems involving transition metal ions, adenosine 5 '-triphosphate, and amino acids

Solution equilibria of the binary and ternary systems involving Mn+ ion, ad enosine 5'-triphosphate, and some mono- and dicarboxylic amino acids (Mn+ = Cu-II, Ni-II, Co-II, La-III, and Ce-III) have been investigated potentiome trically at (25 +/- 0.1) degrees C and I = 0.10 mol dm(-3) (KNO3). The form ation of the different binary and ternary complexes is inferred from the co rresponding titration curves. The stability constants of the various comple xes formed were determined and discussed in terms of the nature of both the metal ion and the ligand. Moreover, the stability of the mixed ligand comp lexes is discussed in relation to that of the corresponding binary complexe s of amino acids.