Interaction of Iron(III) with Succinic Acid and Certain Amino Acids

The interaction in double and triple systems containing Fe³⁺ ion and biologically active compounds—succinic acid and/or certain amino acids (aminoacetic, glutamic, or aspartic)—have been studied by spectrophotometry, pH-potentiometry, and solubility. Composition and stability constants of homo- and mixed-ligand complexes at ionic strength I = 0.3 have been determined; iron(III) succinate with the composition of Fe₂Suc₃∙3H₂O has been isolated, solubility constant of the salt log K_S = –27.74 ± 0.12 has been determined using its solubility data. Redox process proceeded in time has been revealed in iron(III)–succinate anion system.