Jump to main content
Jump to site search

Issue 10, 1998
Previous Article Next Article

Optimisation of a reagentless laccase electrode for the detection of the inhibitor azide†

Abstract

Here we report on the optimisation of a reagentless enzyme sensor for the detection of azide based on the mediated reduction of O2 by a laccase enzyme co-immobilised in a redox hydrogel on electrode surfaces. The sensor response is shown to be influenced by the enzyme loading, the electrolyte pH and ionic strength. The response of the sensor is stable, decreasing by only 25% over a sixteen-hour period. Reproducible inhibition curves for the determination of azide levels from cyclic voltammetric scans can be obtained by normalisation of the sensor response. The resulting enzyme inhibition biosensor can detect levels of azide as low as 2.5 µM under these conditions. Constant potential amperometric detection at the laccase enzyme electrode in a flow injection set-up yields a peak current for inhibition of the mediated reduction of O2. Reproducible peak currents and areas (8.0 and 6.3% RSD, respectively, for n = 11) are obtained for repeated injections of 100 µM azide. Reproducible response curves can be obtained by injection of a 25 mM azide sample and assuming that the peak height and peak area obtained represent 100% inhibition of the enzyme.

Back to tab navigation

Article type: Paper
DOI: 10.1039/A803313G
Citation: Analyst, 1998,123, 1971-1974
  •   Request permissions

    Optimisation of a reagentless laccase electrode for the detection of the inhibitor azide†

    D. Leech and F. Daigle, Analyst, 1998, 123, 1971
    DOI: 10.1039/A803313G

Search articles by author

Spotlight

Advertisements