A sensitive DNA capacitive biosensor using interdigitated electrodes.
A sensitive DNA capacitive biosensor using interdigitated electrodes.
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DOI：
10.1016/j.bios.2016.09.006
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发表时间：
2017-01-15
影响因子：
12.6
通讯作者：
Chen T
中科院分区：
文献类型：
--
作者：
Wang L;Veselinovic M;Yang L;Geiss BJ;Dandy DS;Chen T
本文提出了一种无标记的亲和电容式生物传感器，使用叉指电极。采用优化的DNA探针制备工艺，以减少商业巯基化DNA探针中污染物的影响，用基于西尼罗病毒（Kunjin株）序列的24-核苷酸DNA探针功能化电极表面。该生物传感器具有检测互补DNA片段的能力，检测限低至20个DNA靶分子（1.5 aM范围），使其适用于低靶计数临床应用的实用即时（POC）平台，而无需扩增。将纯化的单链DNA探针寡聚体有效共价固定在清洁的金微电极上，提高了生物传感器检测的重现性。除了低检测限外，该生物传感器还显示出从1 µL−1到105 µL−1目标分子（2000万到200万个目标）的动态检测范围，使其适合在典型的临床应用环境中进行样品分析。本文中提出的结合结果使用荧光寡聚物进行了验证。提出了一种基于叉指电极的电容式DNA生物传感器。它产生超过70 nF的电容变化，响应于少至20个DNA靶标（~1.5 aM）。它的动态范围在1 μL−1到106 μL−1分子（2000万到200万个DNA分子）之间。它在动态范围内实现了良好的线性度。该方法是一种低成本、快速检测POC病原菌的理想方法。
This paper presents a label-free affinity-based capacitive biosensor using interdigitated electrodes. Using an optimized process of DNA probe preparation to minimize the effect of contaminants in commercial thiolated DNA probe, the electrode surface was functionalized with the 24-nucleotide DNA probes based on the West Nile virus sequence (Kunjin strain). The biosensor has the ability to detect complementary DNA fragments with a detection limit down to 20 DNA target molecules (1.5 aM range), making it suitable for a practical point-of-care (POC) platform for low target count clinical applications without the need for amplification. The reproducibility of the biosensor detection was improved with efficient covalent immobilization of purified single-stranded DNA probe oligomers on cleaned gold microelectrodes. In addition to the low detection limit, the biosensor showed a dynamic range of detection from 1 µL−1 to 105 µL−1 target molecules (20 to 2 million targets), making it suitable for sample analysis in a typical clinical application environment. The binding results presented in this paper were validated using fluorescent oligomers. A capacitive DNA biosensor using interdigitated electrodes is presented. It produced more than 70 nF in capacitance change in response to as few as 20 DNA targets (~1.5 aM). It achieved a dynamic range between 1 μL−1 and 106 μL−1 molecules (20 to 2 million DNA molecules). It achieved an excellent linearity within the dynamic range. It is a good candidate for low-cost and rapid detection technology for POC pathogen detection.