Voltammetrically stable water insoluble 3,5-dimethoxy-4-hydroxybenzaldehydrazine (syringaldazine) modified electrode was obtained by sol-gel processing of methyltrimethoxysilane based sol with dissolved syringaldazine together with dispersed graphite particles. This silicate carbon ceramic electrode exhibits stable voltammetry corresponding to the surface confined oxidation-reduction process. The pH dependence of the immobilized syringaldazine redox potential obeys the Nernst equation in the range of 3-10. After further modification with extracellular lyophilized laccase from Cerrena unicolor encapsulated within a thin hydrophilic silicate film the electrode exhibits catalytic activity towards dioxygen reduction. Both catalytic current and potential are pH dependent. (c) 2007 Elsevier B.V. All rights reserved.