Voltammetric determination of DNA hybridization using methylene blue and self-assembled alkanethiol monolayer on gold electrodes
Voltammetric determination of DNA hybridization using methylene blue and self-assembled alkanethiol monolayer on gold electrodes
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DOI：
10.1016/s0003-2670(02)00308-2
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发表时间：
2002-06-26
影响因子：
6.2
通讯作者：
Ozsoz, M
中科院分区：
文献类型：
--
作者：
Kerman, K;Ozkan, D;Ozsoz, M
报道了一种基于固定化互补DNA寡核苷酸杂交检测单链DNA的电化学DNA生物传感器。用N-羟基磺基琥珀酰亚胺（NHS）和N-（3-二甲氨基）丙基-N '-乙基碳二亚胺盐酸盐（EDC）将DNA和寡核苷酸通过DNA碱基上的游离胺共价连接到在金电极（AuE）上预形成的羧酸封端的烷乙醇自组装单分子膜（SAM）上。用微分脉冲伏安法（DPV）研究了固定化DNA分子的表面覆盖率和分子取向。共价固定的探针可以选择性地与靶DNA杂交，以在表面上形成杂交体，尽管碱基被连接到SAM。探针与靶分子杂交后，电活性标记亚甲基蓝（MB）峰电流发生变化。发现峰电流按以下顺序增加：杂交修饰的AuE，错配的杂交修饰的AuE，和探针修饰的AuE，这表明MB信号由暴露的碱基的程度决定。使用非互补DNA序列进行对照实验。还研究了DNA靶浓度对杂交信号的影响。研究了MB与肌苷取代探针的相互作用。传感器的性能特点进行了说明。(C)2002 Elsevier Science B. V.保留所有权利。
An electrochemical DNA biosensor based on the recognition of single stranded DNA (ssDNA) by hybridization detection with immobilized complementary DNA oligonucleotides is presented. DNA and oligonucleotides were covalently attached through free amines on the DNA bases using N-hydroxysulfosuccinimide (NHS) and N-(3-dimethylamino)propyl-N'-ethylcarbodiimide hydrochloride (EDC) onto a carboxylate terminated alkanethiol self-assembled monolayers (SAM) preformed on a gold electrode (AuE). Differential pulse voltammetry (DPV) was used to investigate the surface coverage and molecular orientation of the immobilized DNA molecules. The covalently immobilized probe could selectively hybridize with the target DNA to form a hybrid on the surface despite the bases being attached to the SAM. The changes in the peak currents of methylene blue (MB), an electroactive label, were observed upon hybridization of probe with the target. Peak currents were found to increase in the following order: hybrid-modified AuE, mismatched hybrid-modified AuE, and the probe-modified AuE which indicates the MB signal is determined by the extent of exposed bases. Control experiments were performed using a non-complementary DNA sequence. The effect of the DNA target concentration on the hybridization signal was also studied. The interaction of MB with inosine substituted probes was investigated. Performance characteristics of the sensor are described. (C) 2002 Elsevier Science B.V. All rights reserved.