Bioanalytical utility of sonovoltammetry

Dopamine dissolved within egg homogenate was used as a model system to study the effects of electrode contamination and its subsequent reactivation through ultrasonically mediated in situ cleaning effects. The merits in conducting electroanalytical investigations under the influence of the ultrasonic field were also appraised. Maintaining the ultrasound field during oxidative measurements was found to yield hydrodynamic profiles that were linear over the concentration range 2-20 muM dopamine. The resulting sonolinear sweep voltammograms were compared with conventional rotating disk measurements, with the former found to provide significantly increased limiting currents that were attenuable through the manipulation of the field intensity. The problem of retaining selectivity in the presence of high concentrations of ascorbate was also assessed with the addition of cupric ion prior to commencing the measurements found to efficiently negate an otherwise substantive interference. (C) 2001 Elsevier Science B.V. All rights reserved.