PCFM and GDHPPC labs, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China.
Nanoscale. 2020 Apr 30;12(16):8828-8835. doi: 10.1039/d0nr01025a.
A bright and metal-free mass-amplifying electrochemiluminescence film (MAEF) performing in aqueous media was reported for the first time. Systematic studies demonstrated that the film substrates have a remarkable influence on the electrochemiluminescence (ECL) performance. Gold substrates promote ECL reactions and the subsequent radiative decay process simultaneously, affording an unconventional 507-fold ECL enhancement. Such a gold-enhanced MAEF is opposite to ECL systems previously reported, in which the use of gold electrodes normally results in decreased ECL intensity due to passivation of the gold surface by oxide formation. More importantly, the ECL intensity of the MAEF is linearly amplified through facilely regulating luminogen loading. Morphological analysis reveals that the film consists of grass-like nanowires with a diameter of 57 nm, which facilitate electrical communication between the luminogen, electrode, and supporting electrolyte, giving rise to the mass-amplifying ECL. The bright ECL of the solid film in aqueous media can be readily observed by the naked eye, entirely different from visible ECL systems reported in which ruthenium complexes dissolved/dispersed in solution are used as the luminogens. The film is further utilized to detect dopamine (DA), an important biomolecule related to nervous diseases, in aqueous media, with a low detection limit of 3.3 × 10-16 M. Furthermore, a facile method based on grayscale analysis of ECL images (GAEI) of the film was developed for visual and ultrasensitive DA detection in aqueous media.
一种在水溶液中工作的无金属、大规模放大电化学发光膜（MAEF）被首次报道。系统研究表明，薄膜基底对电化学发光（ECL）性能有显著影响。金基底同时促进 ECL 反应和随后的辐射衰减过程，提供了一种非常规的 507 倍 ECL 增强。这种金增强的 MAEF 与之前报道的 ECL 系统相反，在之前的系统中，由于金表面被氧化物形成钝化，金电极的使用通常会导致 ECL 强度降低。更重要的是，通过简单地调节发光体负载，MAEF 的 ECL 强度可以线性放大。形态分析表明，该膜由直径为 57nm 的草状纳米线组成，这有利于发光体、电极和支持电解质之间的电连通，从而产生大规模放大的 ECL。在水溶液中，固体膜的明亮 ECL 可以用肉眼轻易观察到，这与之前报道的可见 ECL 系统完全不同，可见 ECL 系统中使用的是溶解/分散在溶液中的钌配合物作为发光体。该膜还进一步用于在水溶液中检测多巴胺（DA），一种与神经疾病有关的重要生物分子，检测限低至 3.3×10-16M。此外，还开发了一种基于膜的 ECL 图像灰度分析（GAEI）的简便方法，用于在水溶液中进行可视化和超灵敏的 DA 检测。
