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论文类型：期刊论文

发表时间：2012-10-01

发表刊物：SENSORS AND ACTUATORS B-CHEMICAL

收录刊物：SCIE、EI、Scopus

卷号：173

页面范围：477-482

ISSN号：0925-4005

关键字：Fluorescent biosensor; Catecholics detection; Extradiol dioxygenase; Quantum dots

摘要：In this paper, a new type of fluorescent biosensing system for catechol and 2,3-dihydroxybiphenyl (DHB) was described based on the inner filter effect (IFE), with the combination of CdTe quantum dots (QDs) and an extradiol dioxygenase, 2,3-dihydroxybiphenyl 1,2-dioxygenase (BphC). In the presence of BphC and its substrates, catechol and DHB, the excitation of QDs was partially weakened by the competitive absorption of the enzymatic reaction products, resulting in the quenching of QDs. The dependence of the emission intensity quenching on "quencher" concentration obeyed the quadratic equation, and the detection limits for catechol and DHB were 0.02 and 2 mu M, respectively. The present QD-BphC system also exhibited good selectivity to either catechol or DHB in the mixtures of other phenolic compounds. However, when catechol and DHB coexisted, the QD-BphC system could not separate the signals of these two compounds from each other due to the inherent substrate range of BphC. Nevertheless, the developed BphC-based fluorescent biosensor via the IFE on fluorescence of QDs could be employed as a robust support for the construction of other enzyme-based biosensors. (C) 2012 Elsevier B.V. All rights reserved.