MIIT Key Laboratory of Advanced Display Materials and Devices, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
MIIT Key Laboratory of Advanced Display Materials and Devices, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Biosens Bioelectron. 2017 Nov 15;97:1-7. doi: 10.1016/j.bios.2017.05.033. Epub 2017 May 18.
For the efficient surface plasmon resonance (SPR)-based DNA assay researching, signal amplification tactics were absolutely necessary. In this work, a sensitive SPR-DNA sensor was developed by employing in situ synthesis of copper nanoparticles (CuNPs) templated by poly-T sequences DNA from terminal deoxynucleotidyl transferase (TdT)-mediated extension, and synergistically with nano-effect deposition as the mass relay. The objective of this strategy was manifold: firstly, tDNA hybridized with the optimal designed probes to active the TdT-mediated DNA extension onto the surface of SPR chip, resulted a long poly-T sequences ssDNA chain in dsDNA terminal onto surface of gold chip and characterized by SPR signal amplitudes. Secondly, copper ion (Cu) adsorbed into the skeleton of poly-T sequences DNA, with the aid of ascorbic acid (VC) to achieve the Cu reduction, copper nanostructures (CuNPs) was synchronously generated onto the single nucleotide chain anchoring in dsDNA derivatives and the formation was featured by transmission electron micrographs (TEM) and electrochemistry. Lastly, dsDNA-complexed CuNPs (CuNPs@dsDNA) triggered the final signal amplification via real-time conversion of the additive catechol violet (CV) into oligomer or chelation precipitation by CuNPs-tagged reporters. With the proposed setups, a precise and replicable DNA sensing platform for specific target oligo was obtained with a detection limit down to 3.21 femtomolar, demonstrating a beneficial overlapping exploitation of nanomaterials and biochemical reaction as unique SPR infrastructure. Such triple-amplification strategic setups, the possibility of various methods abutment and biocompatibility weight reactor was amassed and adapted to more biological detection field.
为了实现高效的表面等离子体共振（SPR）基 DNA 分析，信号放大策略是绝对必要的。在这项工作中，通过采用末端脱氧核苷酸转移酶（TdT）介导的延伸中聚-T 序列 DNA 模板原位合成铜纳米粒子（CuNPs），并协同纳米效应沉积作为质量继电器，开发了一种灵敏的 SPR-DNA 传感器。该策略的目的是多方面的：首先，tDNA 与最佳设计的探针杂交，激活 TdT 介导的 DNA 延伸到 SPR 芯片表面，导致 dsDNA 末端的长聚-T 序列 ssDNA 链与金芯片表面结合，并通过 SPR 信号幅度进行表征。其次，铜离子（Cu）吸附到聚-T 序列 DNA 的骨架中，在抗坏血酸（VC）的帮助下实现 Cu 的还原，在 dsDNA 衍生物中锚定的单核苷酸链上同步生成铜纳米结构（CuNPs），并通过透射电子显微镜（TEM）和电化学进行特征描述。最后，dsDNA 复合的 CuNPs（CuNPs@dsDNA）通过实时将外加儿茶酚紫（CV）转化为寡聚物或通过 CuNPs 标记的报告分子进行螯合沉淀，引发最终的信号放大。利用所提出的方案，获得了针对特定寡核苷酸的精确和可重复的 DNA 传感平台，检测限低至 3.21 飞摩尔，证明了纳米材料和生化反应作为独特的 SPR 基础设施的有益重叠利用。这种三重放大策略设置，为更多的生物检测领域积累并适应了多种方法的支撑和生物相容性重量反应器的可能性。
