Ultramicroelectrode voltammetric investigation of the micellar phase of sodium dodecyl sulfate in aqueous solution

Ultramicroelectrode voltammetric measurements have been made on Sodium Dodecyl Sulfate (SDS) in aqueous solutions using K4Fe(CN)(6) as the electroactive probe and H2SO4 as the supporting electrolyte. By extrapolation, the SDS micellar diffusion coefficient (D-m) hydrodynamic radius (R-m), aggregation number (n), and the molecular weight of SDS micellar in aqueous solutions at various surfactant concentrations are obtained. The partition coefficients, K-D, of the electroactive probe between micelle and water continuous phase are also estimated. The results suggest that the probe is sensitive to the surfactant concentration and reflect the changes of the structure and the hydrophobic nature of micelles.