A straightforward, cost-effective and biocompatible reduction approach was applied to fabricate soluble but non-luminous glutathione-stabilized copper nanocluster (GSH-CuNCs). Surprisingly, as high as 1 × 10³ times fluorescence enhancement was acquired when Ce³⁺ was injected at an extremely low concentration of only 18 µM. Ce³⁺ outperformed other rare-earth metal ions in terms of inducing fluorescence amplification of the non-luminous GSH-CuNCs. Furthermore, Ce³⁺ was employed as inducer for aggregation-induce emission (AIE) effect as well as reactant to coordinate with target of 2,6-pyridine dicarboxylic acid (DPA) due to the stronger coordination ability between Ce³⁺ and DPA than that of Ce³⁺ and GSH. As a result, the Ce³⁺/GSH-CuNCs ensemble was developed as a novel sensor to detect DPA in the "on–off" mode. When DPA was introduced into the sensor, Ce³⁺ failed to interact with GSH and detached from the surface of GSH-CuNCs, leading to fluorescence quenching. In addition, static quenching process and internal filtration effect (IFE) between Ce³⁺/GSH-CuNCs and DPA were also responsible for fluorescence quenching effect. A good linear relationship was obtained from 0.3 µM to 18 µM, with a limit of detection (LOD) of 0.19 µM. The as-proposed probe displayed high specificity to DPA and provided a simple, fast rapid and cheap method for construction this type of ensemble sensors to detect other targets.

一种简单、经济高效且具有生物相容性的还原方法被应用于制造可溶性但不发光的谷胱甘肽稳定铜纳米团簇 (GSH-CuNC)。令人惊讶的是，当以仅 18 µM 的极低浓度注入Ce ³⁺时，获得了高达 1 × 10 ^{3倍的荧光增强。}Ce ³⁺在诱导不发光的GSH-CuNCs的荧光放大方面优于其他稀土金属离子。此外，由于 Ce ³⁺和 DPA 之间的配位能力比Ce 3+ 更强，因此 Ce ³⁺被用作聚集诱导发光 (AIE) 效应的诱导剂以及与 2,6-吡啶二甲酸 (DPA) 靶标配位的反应物。Ce ³⁺和谷胱甘肽。因此，Ce ³⁺ /GSH-CuNCs 系综被开发为一种新型传感器，可在“开-关”模式下检测 DPA。当 DPA 被引入传感器时，Ce ³⁺无法与 GSH 相互作用并从 GSH-CuNCs 表面脱离，导致荧光猝灭。此外，Ce ³⁺ /GSH-CuNCs 和DPA 之间的静态猝灭过程和内部过滤效应(IFE) 也是荧光猝灭作用的原因。在 0.3 µM 至 18 µM 范围内获得了良好的线性关系，检测限 (LOD) 为 0.19 µM。所提出的探针对 DPA 显示出高特异性，并为构建此类集成传感器以检测其他目标提供了一种简单、快速、廉价的方法。