Investigation of biosensor signal bioamplification: Comparison of direct electrochemistry phenomena of individual Laccase, and dual Laccase-Tyrosinase copper enzymes, at a Sonogel-Carbon electrode

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• 作者：Mohammed ElKaoutit ; Ignacio Naranjo-Rodriguez ; Khalid Riffi Temsamani ; Manuel Domí ; nguez ; Jose Luis Hidalgo-Hidalgo de Cisneros
• 关键词：Dual enzymes based biosensor ; Direct electrochemistry ; Signal bioamplification ; Sonogel-Carbon electrode
• 刊名：Talanta
• 出版年：2008
• 出版时间：15 June 2008
• 年：2008
• 卷：75
• 期：5
• 页码：1348-1355
• 全文大小：738 K

文摘

Direct electrochemistry of Trametes versicolor Laccase (LAC) was found at a Sonogel-Carbon electrode. The bioamplification, performed by dual immobilization of this enzyme and Mushroom Tyrosinase (TYR), of the bio-electrocatalytic reduction of O₂ was investigated. The calculated transfer coefficients were 0.64 and 0.67, and the heterogeneous electron-transfer rate constants were 6.19 and 8.52 s⁻¹, respectively, for the individual LAC and dual LAC-TYR-based Nafion/Sonogel-Carbon bio-electrodes. The responses of the dual enzymes electrode to polyphenols were stronger than those of the individual LAC or TYR biosensors. Hypotheses are offered about the mechanism of bioamplification. The surfaces of the biosensors were also characterized by AFM.