Bioanalytical utility of sonovoltammetry

Dopamine dissolved within egg homogenate was used as a model system to stud y the effects of electrode contamination and its subsequent reactivation th rough ultrasonically mediated in situ cleaning effects. The merits in condu cting electroanalytical investigations under the influence of the ultrasoni c field were also appraised. Maintaining the ultrasound field during oxidat ive measurements was found to yield hydrodynamic profiles that were linear over the concentration range 2-20 muM dopamine. The resulting sonolinear sw eep voltammograms were compared with conventional rotating disk measurement s, with the former found to provide significantly increased limiting curren ts that were attenuable through the manipulation of the field intensity. Th e problem of retaining selectivity in the presence of high concentrations o f ascorbate was also assessed with the addition of cupric ion prior to comm encing the measurements found to efficiently negate an otherwise substantiv e interference. (C) 2001 Elsevier Science B.V. All rights reserved.