Application of Capillary Electrophoresis for Determination of Stability constants of Complexes of Iron (III) with Sulfosalicylic Acid with a 1:1 and 1:2 Stoichiometries

Capillary electrophoresis was employed for the determination of stability constants of complexes of iron (III) with sulfosalicylic acid with a 1:1 and 1:2 stoichiometries. Sulfosalicylic acid was used as background electrolyte and ligand in order to prevent occurrence of system peaks. In the pH range of background electrolyte from 2,5 to 3, the experimental dependences of electrophoretic mobility complexes on ligand concentration were obtained. The ratio of the stability constants lg (beta(2)/beta(l)) for complexes of iron (III) with sulfosalicylic acid was calculated. The obtained value was 10,7 +/- 0,1, which agrees well with literature data.