Determination of stability constants of iron(III) and chromium(III)-nitrilotriacetate-methyl cysteine mixed complexes by electrophoretic technique

Abstract

The stability constants of Fe(III) and Cr(III) with methyl cysteine and nitrilotriacetate (NTA) were determined by paper electrophoretic technique. Beside binary  ternary complexes have also been studied, in which nitrilotriacetate and methyl cysteine acts as primary and secondary ligand, respectively. The stability constants of mixed ligand complexes metal (M)-nitrilotriacetate-methyl cysteine have been found to be 5.72 ± 0.09 and 5.54 ± 0.11 (log K values) for Fe(III) and Cr(III) complexes, respectively, at 35 ^oC and ionic strength 0.1 M.

KEY WORDS: Paper electrophoresis, Iron(III) complexes, Chromium(III) complexes, Mixed ligand metal complexes, Stability constants, Nitrilotriacetic acid, Methyl cysteine

Bull. Chem. Soc. Ethiop. 2004, 18(1), 29-36.