Fe2O3@Au core/shell nanoparticle-based electrochemical DNA biosensor for Escherichia coli detection
Fe2O3@Au core/shell nanoparticle-based electrochemical DNA biosensor for Escherichia coli detection
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DOI：
10.1016/j.talanta.2010.12.042
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发表时间：
2011-05-15
期刊：
影响因子：
6.1
通讯作者：
Jin, Litong
中科院分区：
文献类型：
--
作者：
Li, Kang;Lai, Yanjun;Jin, Litong
以Fe2O3@Au核/壳结构纳米粒子为载体，构建了一种电化学DNA生物传感器，用于检测大肠杆菌（Escherichia coli，E.大肠杆菌）。通过在Fe 2 O3纳米粒子表面还原HAuCl 4，制备了磁性Fe2O3@Au纳米粒子。该DNA生物传感器基于夹心检测策略，包括固定在磁性纳米颗粒（MNP）上的捕获探针、辣根过氧化物酶（HRP）标记的靶探针和报告探针。一旦加入磁场，这些夹心复合物被磁性分离，限制在MNP表面的HRP可以催化酶底物并产生电化学信号。该传感器可检测浓度大于0.01pM的DNA靶和浓度大于500 cfu/mL的E.大肠杆菌中，而无需任何核酸扩增步骤。方法的检出限可达5cfu/mL。大肠杆菌中。(C)2011 Elsevier B. V.保留所有权利。
A Fe2O3@Au core/shell nanoparticle-based electrochemical DNA biosensor was developed for the ampermetric detection of Escherichia coli (E. coli). Magnetic Fe2O3@Au nanoparticles were prepared by reducing HAuCl4 on the surfaces of Fe2O3 nanoparticles. This DNA biosensor is based on a sandwich detection strategy, which involves capture probe immobilized on magnetic nanoparticles (MNPs), target and reporter probe labeled with horseradish peroxidase (HRP). Once magnetic field was added, these sandwich complexes were magnetically separated and HRP confined at the surfaces of MNPs could catalyze the enzyme substrate and generate electrochemical signals. The biosensor could detect the concentrations upper than 0.01 pM DNA target and upper than 500 cfu/mL of E. coli without any nucleic acid amplification steps. The detection limit could be lowered to 5 cfu/mL of E. coli after 4.0 h of incubation. (C) 2011 Elsevier B.V. All rights reserved.