Rho Sangchul, Jahng Deokjin, Lim Jae Hoon, Choi Jinsub, Chang Jeong Ho, Lee Sang Cheon, Kim Kyung Ja
Department of Environmental Engineering and Biotechnology, Myongji University, Yongin, Gyunggi-do 449-728, South Korea.
Biosens Bioelectron. 2008 Jan 18;23(6):852-6. doi: 10.1016/j.bios.2007.09.001. Epub 2007 Sep 11.
Electrochemical DNA biosensors based on a thin gold film sputtered on anodic porous niobium oxide (Au@Nb(2)O(5)) are studied in detail here. We found that the novel DNA biosensor based on Au@Nb(2)O(5) is superior to those based on the bulk gold electrode or niobium oxide electrode. For example, the novel method does not require any time-consuming cleaning step in order to obtain reproducible results. The adhesion of gold films on the substrate is very stable during electrochemical biosensing, when the thin gold films are deposited on anodically prepared nanoporous niobium oxide. In particular, the novel biosensor shows enhanced biosensing performance with a 2.4 times higher resolution and a three times higher sensitivity. The signal enhancement is in part attributed to capacitive interface between gold films and nanoporous niobium oxide, where charges are accumulated during the anodic and cathodic scanning, and is in part ascribed to the structural stability of DNA immobilized at the sputtered gold films. The method allows for the detection of single-base mismatch DNA as well as for the discrimination of mismatch positions.
本文详细研究了基于溅射在阳极多孔氧化铌（Au@Nb₂O₅）上的薄金膜的电化学DNA生物传感器。我们发现，基于Au@Nb₂O₅的新型DNA生物传感器优于基于块状金电极或氧化铌电极的传感器。例如，该新方法无需任何耗时的清洗步骤即可获得可重复的结果。当在阳极制备的纳米多孔氧化铌上沉积薄金膜时，金膜在基底上的附着力在电化学生物传感过程中非常稳定。特别是，新型生物传感器表现出增强的生物传感性能，分辨率提高了2.4倍，灵敏度提高了三倍。信号增强部分归因于金膜与纳米多孔氧化铌之间的电容性界面，在阳极和阴极扫描过程中电荷在该界面积累，部分归因于固定在溅射金膜上的DNA的结构稳定性。该方法能够检测单碱基错配DNA以及区分错配位置。
