School of Materials Science and Chemical Engineering, The State Key Laboratory Base of Novel Functional Materials and Preparation Science, Ningbo University, Ningbo 315211, PR China.
Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Division of Polymer and Composite Materials, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo 315201, PR China; Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
Biosens Bioelectron. 2018 Oct 30;118:247-252. doi: 10.1016/j.bios.2018.07.064. Epub 2018 Jul 31.
Here, a novel Faraday cage-type electrochemiluminescence (ECL) biosensor was presented for simultaneous determination of miRNA-141 and miRNA-21 based on the potential-resolved strategy. In this work, capture units were prepared by immobilizing hairpin DNA1 (HP1) and hairpin DNA2 (HP2) on FeO @Au nanocomposites, while g-CN @AuNPs nanocomposites labelled by signal DNA1 (sDNA1) and ruthenium-based metal organic framework (Ru-MOF) nanosheets labelled by signal DNA2 (sDNA2) were used as signal units. In this proposed biosensor, signal units g-CN @AuNPs-sDNA1 and Ru-MOF-sDNA2 could exhibit two strong and stable ECL emissions at - 1.4 V and + 1.5 V respectively, which could be used as effective potential-resolved signal tags. Moreover, taking advantage of the proposed Faraday cage-type model, all electrochemiluminophores in the signal units could take part in electrode reactions, the signal units became part of the electrode surface and extended the outer Helmholtz plane (OHP) of the proposed electrode, and then the detection sensitivity was improved greatly. Accordingly, dual targets miRNA-141 and miRNA-21 could be detected within the linear range of 1 fM to 10 pM, with the detection limit of 0.3 fM. Meanwhile, the proposed miRNA assay exhibited high selectivity and sensitivity, even for practical analysis in human serum. So, this potential-resolved ECL biosensor is proved to be a feasible tool for dual targets detection of miRNAs in clinical diagnosis.
这里，提出了一种新颖的法拉第笼型电化学发光（ECL）生物传感器，用于基于电位分辨策略同时测定 miRNA-141 和 miRNA-21。在这项工作中，通过将发夹 DNA1（HP1）和发夹 DNA2（HP2）固定在 FeO@Au 纳米复合材料上制备捕获单元，而用信号 DNA1（sDNA1）标记的 g-CN@AuNPs 纳米复合材料和用信号 DNA2（sDNA2）标记的基于钌的金属有机骨架（Ru-MOF）纳米片被用作信号单元。在这个提出的生物传感器中，信号单元 g-CN@AuNPs-sDNA1 和 Ru-MOF-sDNA2 可以分别在-1.4 V 和+1.5 V 处呈现出两个强而稳定的 ECL 发射，它们可以用作有效的电位分辨信号标签。此外，利用所提出的法拉第笼型模型，信号单元中的所有电化学发光体都可以参与电极反应，信号单元成为电极表面的一部分，并扩展了所提出电极的外亥姆霍兹平面（OHP），从而大大提高了检测灵敏度。因此，双靶标 miRNA-141 和 miRNA-21 可以在 1 fM 至 10 pM 的线性范围内检测，检测限为 0.3 fM。同时，所提出的 miRNA 测定法表现出高选择性和灵敏度，即使在实际的人血清分析中也是如此。因此，这种电位分辨 ECL 生物传感器被证明是临床诊断中 miRNA 双靶标检测的一种可行工具。
