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Substrate specificity and interferences of a direct-electron-transfer-based glucose biosensor.

ABSTRACT: Electrochemical sensors for glucose monitoring employ different signal transduction strategies for electron transfer from the biorecognition element to the electrode surface. We present a biosensor that employs direct electron transfer and evaluate its response to various interfering substances known to affect glucose biosensors.The enzyme cellobiose dehydrogenase (CDH) was adsorbed on the surface of a carbon working electrode and covalently bound by cross linking. The response of CDH-modified electrodes to glucose and possible interfering compounds was measured by flow-injection analysis, linear sweep, and chronoamperometry.Chronoamperometry showed initial swelling/wetting of the electrode. After stabilization, the signal was stable and a sensitivity of 0.21 µA mM-1 cm-2 was obtained. To investigate the influence of the interfering substances on the biorecognition element, the simplest possible sensor architecture was used. The biosensor showed little (<5% signal deviation) or no response to various reported electroactive or otherwise interfering substances.Direct electron transfer from the biorecognition element to the electrode is a new principle applied to glucose biosensors, which can be operated at a low polarization potential of -100 mV versus silver/silver chloride. The reduction of interferences by electrochemically active substances is an attractive feature of this promising technology for the development of continuous glucose biosensors.

SUBMITTER: Felice AK

PROVIDER: S-EPMC3869135 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Substrate specificity and interferences of a direct-electron-transfer-based glucose biosensor.

Felice Alfons K G AK Sygmund Christoph C Harreither Wolfgang W Kittl Roman R Gorton Lo L Ludwig Roland R

Journal of diabetes science and technology 20130501 3

<h4>Objective</h4>Electrochemical sensors for glucose monitoring employ different signal transduction strategies for electron transfer from the biorecognition element to the electrode surface. We present a biosensor that employs direct electron transfer and evaluate its response to various interfering substances known to affect glucose biosensors.<h4>Methods</h4>The enzyme cellobiose dehydrogenase (CDH) was adsorbed on the surface of a carbon working electrode and covalently bound by cross linki ...[more]

PMID: 23759400

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Substrate specificity and interferences of a direct-electron-transfer-based glucose biosensor.

Publications

Substrate specificity and interferences of a direct-electron-transfer-based glucose biosensor.

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