Sensing of double-stranded DNA molecules by their intrinsic molecular charge using the light-addressable potentiometric sensor
Sensing of double-stranded DNA molecules by their intrinsic molecular charge using the light-addressable potentiometric sensor
复制标题
使用光可寻址电位传感器通过其内在分子电荷感测双链 DNA 分子
DOI：
10.1016/j.snb.2016.02.004
复制
发表时间：
2016-06-28
影响因子：
8.4
通讯作者：
Schoening, Michael J.
中科院分区：
文献类型：
--
作者：
Wu, Chunsheng;Poghossian, Arshak;Schoening, Michael J.
基于半导体场效应器件的多光斑光寻址电位传感器（LAPS），利用双链脱氧核糖核酸（dsDNA）分子的固有电荷，实现了对dsDNA分子的无标记检测。为了减少DNA电荷和传感器表面之间的距离，从而增强dsDNA分子和LAPS之间的静电耦合，将带负电荷的dsDNA分子静电吸附到覆盖有带正电荷的弱PAH（聚（烯丙胺盐酸盐））层的LAPS的栅极表面上。通过光电流-电压和恒光电流测量，记录了PAH/dsDNA双层膜逐层吸附引起的LAPS每个点的表面电位变化。此外，通过原子力显微镜测量研究了连续静电吸附PAH和双链DNA层之前和之后的栅极表面的表面形态。此外，荧光显微镜用于验证双链DNA分子成功吸附到PAH修饰的LAPS表面上。在吸附10 nM dsDNA分子后，记录到25 mV的高传感器信号。检测下限低至0.1 nM dsDNA。所获得的结果表明，PAH修饰的LAPS装置提供了一个方便和快速的平台，用于直接无标记的电检测溶液中杂交的dsDNA分子。(c)2016爱思唯尔B. V.保留所有权利。
A multi-spot light-addressable potentiometric sensor (LAPS), which belongs to the family of semiconductor field-effect devices, was applied for label-free detection of double-stranded deoxyribonucleic acid (dsDNA) molecules by their intrinsic molecular charge. To reduce the distance between the DNA charge and sensor surface and thus, to enhance the electrostatic coupling between the dsDNA molecules and the LAPS, the negatively charged dsDNA molecules were electrostatically adsorbed onto the gate surface of the LAPS covered with a positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)). The surface potential changes in each spot of the LAPS, induced by the layer-by-layer adsorption of a PAH/dsDNA bilayer, were recorded by means of photocurrent-voltage and constant-photocurrent measurements. In addition, the surface morphology of the gate surface before and after consecutive electrostatic adsorption of PAH and dsDNA layers was studied by atomic force microscopy measurements. Moreover, fluorescence microscopy was used to verify the successful adsorption of dsDNA molecules onto the PAH-modified LAPS surface. A high sensor signal of 25 mV was registered after adsorption of 10 nM dsDNA molecules. The lower detection limit is down to 0.1 nM dsDNA. The obtained results demonstrate that the PAH-modified LAPS device provides a convenient and rapid platform for the direct label-free electrical detection of in-solution hybridized dsDNA molecules. (c) 2016 Elsevier B.V. All rights reserved.