Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Tabuk, Tabuk 71491, Saudi Arabia.
Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Assiut University, Assiut, 71526, Egypt.
Anal Methods. 2024 Nov 21;16(45):7744-7751. doi: 10.1039/d4ay01525h.
The development of dual-emission ratiometric fluorescent probes with aggregation-induced emission enhancement (AIEE) overcomes the limitations of gold nanocluster (Au NC)-based probes, particularly their weak intrinsic fluorescence, in real-world applications. These AIEE probes also exhibit superior detection limits and enhanced sensitivity. A novel combination for the reliable fluorometric detection of glutathione (GSH) was proposed, utilizing aggregation-induced emission enhancement (AIEE) facilitated by electrostatic interaction and spatial confinement. The probe consists of a ratiometric combination of negatively charged α-lipoic acid-modified Au NCs (LA@Au NCs) and positively charged silicon nanoparticles (SiNPs). The addition of SiNPs causes aggregation of LA@Au NCs, enhancing the fluorescence of LA@Au NCs through the AIE effect under electrostatic interaction and spatial confinement. The addition of Cu quenched the emission of LA@Au NCs as a result of charge transfer. The fluorescence emissions of LA@Au NCs were restored upon the addition of GSH due to the interaction between GSH and Cu. Simultaneously, the emission signal of SiNPs remains unchanged, serving as an internal reference signal during GSH measurement. It was found that the fluorescence ratio (/) is directly proportional to the concentration of GSH in the range of 0.05-100 μM, with a detection limit of 1.7 nM (S/N = 3). The proposed system was applied to detect GSH in real samples, including dietary supplements, human serum, and saliva samples. This work opens new avenues for constructing novel sensors based on AIEE for detecting biomolecules.
具有聚集诱导发射增强（AIEE）效应的双发射比率荧光探针的发展克服了基于金纳米簇（Au NC）探针的局限性，特别是其较弱的固有荧光，在实际应用中。这些 AIEE 探针还表现出优越的检测限和增强的灵敏度。提出了一种新的组合，用于可靠的荧光检测谷胱甘肽（GSH），利用静电相互作用和空间限制促进的聚集诱导发射增强（AIEE）。该探针由带负电荷的α-硫辛酸修饰的 Au NCs（LA@Au NCs）和带正电荷的硅纳米粒子（SiNPs）的比率组合组成。添加 SiNPs 会导致 LA@Au NCs 聚集，通过静电相互作用和空间限制下的 AIE 效应增强 LA@Au NCs 的荧光。添加 Cu 会由于电荷转移而猝灭 LA@Au NCs 的发射。由于 GSH 与 Cu 之间的相互作用，添加 GSH 后 LA@Au NCs 的荧光发射得以恢复。同时，SiNPs 的发射信号保持不变，在 GSH 测量过程中作为内部参考信号。结果发现，荧光比（/）与 0.05-100 μM 范围内 GSH 的浓度呈正比，检测限为 1.7 nM（S/N = 3）。该系统被应用于检测真实样品中的 GSH，包括膳食补充剂、人血清和唾液样品。这项工作为基于 AIEE 构建用于检测生物分子的新型传感器开辟了新途径。
