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Indexed by:期刊论文

Date of Publication:2011-07-15

Journal:BIOSENSORS & BIOELECTRONICS

Included Journals:SCIE、EI、PubMed

Volume:26

Issue:11

Page Number:4362-4367

ISSN No.:0956-5663

Key Words:Biosensor; Catechol; Extradiol dioxygenase; SiO2 sol-gel; Detection

Abstract:A feasible and sensitive biosensor for catechol and its derivatives using 2,3-dihydroxybiphenyl 1,2-dioxygenase (BphC)-modified glassy carbon electrode was successfully constructed by polyvinyl alcohol-modified SiO2 sol-gel method. The as-prepared biosensor was characterized by electrochemical impedance spectroscopy, and the surface topography of the film was imaged by atomic force microscope. Liquid chromatography-tandem mass spectrometry was applied to reveal the catalytic mechanism. BphC embedded in SiO2 gel maintained its bioactivity well and exhibited excellent eletrocatalytical response to both catechol and some of its derivatives (such as 3-methylcatechol and 4-methylcatechol). The biosensor showed a linear amperometric response range between 0.002 mM and 0.8 mM catechol. And the sensitivity was 1.268 mA/(mM cm(2)) with a detection limit of 0.428 mu M for catechol (S/N = 3). Furthermore, the BphC biosensor exhibited perfect selectivity for catechol in the mixtures of catechol and phenol. It was suggested that this flexible protocol would open up a new avenue for designing other ring-cleavage enzyme biosensors, which could be widely used for monitoring various kinds of environmental pollutants. (C) 2011 Elsevier B.V. All rights reserved.