Metal ions play an important role in biological system. The importance of metal ions to essential functions of living systems and for wellbeing of living organisms is well known. Metal ions are fundamental elements for the maintenance of life spans of the human, animals, and plants. Recent advances in inorganic chemistry have made possible formation of number of transition metal complexes with organic ligand of interest, which can be used as therapeutic agent. In coordination compounds studies, knowledge of the stability constants of complexes is necessary for preliminary quantitative treatment. The present technique involving the use of paper electrophoresis is described for the study of equilibria in binary complex systems in solution. The method is based on the movement of a spot of a metal ion in an electric field at various pH’s of background electrolyte. A graph of pH versus mobility was used to obtained information in the binary complexes and to calculate its stability constants. Using this method , the stability constants of binary complexes metal (II) – α – aminobutenoic acid have been determined to be ( 3.78 ± 0.01, 2.48 ± 0.03 ); ( 3.27 ± 0.04, 2.33 ± 0.07 ); and (4.45 ± 0.02, 2.66 ± 0.05); (logarithm stability constant values) for cadmium (II), iron (II) and zinc (II) complexes, respectively, at ionic strength 0.01 Mol / L and a temperature of 35º C.
Keywords: Paper electrophoresis; Overall mobility; Metal complexes; Stability constants.