Electrochemistry and application of a novel\ud monosubstituted squarate electron-transfer\ud mediator in a glucose oxidase-doped\ud poly(phenol) sensor\ud \ud

摘要

Electrosynthetic poly(phenol) nanofilms were deposited in situ on platinum electrodes\udin the presence and absence of glucose oxidase. The synthesis charges and currents of\udthe nonconducting polymer films were recorded at various applied potentials for films grown\udfrom 25–100 mM phenol concentrations. Film parameters such as the standard rate constant\udfor film deposition, film thickness, and surface concentration of the poly(phenol) films were\udevaluated from the cyclic and step voltammograms of the polymerization process. A novel\udelectron-transfer mediator consisting of monosubstituted 4-hydroxycyclobut-3-ene-1,2-dione\ud(squarate) was used as a mediator for Pt/poly(phenol) nano-film/GOx amperometric glucose\udbiosensors. Amperometric responses for 3-diphenylamino-4-hydroxycyclobut-3-ene-1,2-\uddione (diphenylaminosquarate: E°′ = of +328 mV/Ag-AgCl at pH 7.0)-mediated systems\udwere measured by both steady-state amperometric and cyclic voltammetry. The sensor sensitivity\udwas calculated to be 558 nA cm\ud–2\ud(µM)\ud–1\ud.\ud\ud