Key Laboratory of Luminescence Analysis and Molecular Sensing, Southwest University, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China.
Key Laboratory of Luminescence Analysis and Molecular Sensing, Southwest University, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China.
Biosens Bioelectron. 2022 Oct 15;214:114506. doi: 10.1016/j.bios.2022.114506. Epub 2022 Jun 26.
In this work, the electrochemiluminescence (ECL) phenomenon of three-dimensional graphitic carbon nitride (3D g-CN) was reported. Firstly, the proposed 3D g-CN possessed 3D porous interconnected open-framework which enabled faster charge transport and efficient penetration of co-reactants due to "pore confinement effect". Then, we found that the dissolved O could serve as an excellent co-reactant for cathodic ECL of 3D g-CN. And the high specific surface area was beneficial to better adsorbing and gathering of dissolved O and reactive oxygen species (ROSs), which made them full contact on the surface or inside of 3D g-CN, giving a more sufficient ECL reaction and higher ECL signal. Based on the proposed 3D g-CN-O ECL system, a sensitive biosensor was constructed for microRNA-21 (miRNA-21) detection with assistance of 3D spherical tracks assisted 3D DNA walking machine, which exhibited superior performance for miRNA-21 with detection limit of 0.22 fM. The proposed 3D g-CN-O ECL system with high ECL efficiency and the effective target conversion and amplification strategies were beneficial to construct ultra-sensitive ECL sensing platform, which would be better applied to clinical bioanalysis.
在这项工作中，报道了三维石墨相氮化碳（3D g-CN）的电致化学发光（ECL）现象。首先，所提出的 3D g-CN 具有 3D 多孔互连的开放式骨架，由于“孔限制效应”，能够实现更快的电荷传输和有效的共反应物渗透。然后，我们发现溶解的 O 可以作为 3D g-CN 阴极 ECL 的极好共反应物。高比表面积有利于更好地吸附和聚集溶解的 O 和活性氧物质（ROSs），使它们在 3D g-CN 的表面或内部充分接触，从而进行更充分的 ECL 反应和更高的 ECL 信号。基于所提出的 3D g-CN-O ECL 系统，借助 3D 球形轨道辅助 3D DNA 行走机，构建了用于 microRNA-21（miRNA-21）检测的灵敏生物传感器，对 miRNA-21 具有优异的检测性能，检测限低至 0.22 fM。具有高 ECL 效率的所提出的 3D g-CN-O ECL 系统以及有效的目标转化和放大策略有利于构建超灵敏的 ECL 传感平台，这将更好地应用于临床生物分析。
