A Fast and Direct Amperometric Determination of Hg2+ by a Bienzyme Electrode Based on the Competitive Activities of Glucose Oxidase and Laccase
By: Cosnier, Serge; Mousty, Christine; Guelorget, Amandine; Lopez, Marta Sanchez-Paniagua; Shan., Dan
A new concept of enzyme inhibition-based biosensor involving the appearance of an amperometric signal for an inhibition by mercury was developed. The bienzyme sensor was composed of two layers of clay materials. The inner layer was constituted of layered double hydroxides entrapping laccase wired by ABTS. The outer laponite layer contained glucose oxidase (GOD). GOD catalyzed the glucose oxidn. with the redn. of O2 into H2O2. This induced a drastic decrease of the biosensor response to O2 by the elec. wired laccase. HgCl2 inhibited the O2 consumption by GOD leading to a signal increase of the electroenzymic redn. of O2.