The Key Laboratory of Luminescence and Real-time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China.
The Key Laboratory of Chongqing Inorganic Special Functional Materials, College of Chemistry and Chemical Engineering, Yangtze Normal University, Chongqing, 408100, China.
Anal Chim Acta. 2018 Sep 18;1024:145-152. doi: 10.1016/j.aca.2018.04.016. Epub 2018 Apr 18.
Contrary to organic solvent-induced aggregation of Au nanoclusters (AuNCs), herein, we reported aggregation induced emission enhancement (AIEE) of AuNCs in an aqueous media through confinement of AuNCs by in situ formed Zn-MOF for detecting Zn. Glutathione capped AuNCs (GSH-AuNCs) was synthesized through reduction of Au by glutathione. Zn could significantly enhance the fluorescence of GSH-AuNCs upon addition of 2-methylimidazole, which was attributed to the formation of Zn-MOF. XRD and TEM were used to characterize the in situ formed Zn-MOF. Zn induced aggregation was demonstrated by dynamic light scattering and TEM. The quantum yields (QYs) of AuNCs after aggregation induced by in situ formed Zn-MOF attained to 36.6%, which was nearly 9 times that of the sole AuNCs. On this basis, a fluorogenic sensor was reported for Zn detection with a linear range from 12.3 nM to 24.6 μM and a detection limit of 6 nM (S/N = 3). The proposed sensor was successfully applied to assay the content of zinc in human serum, milk, water, and zinc sulfate syrup oral solution samples. The novel strategy proposed in this work may open a new window of interest in an unconventional application of gold nanoclusters/MOF nanoscale platform for metal ion detection and nutritional assessment of food.
与有机溶剂诱导的金纳米团簇（AuNCs）聚集相反，本文报道了通过原位形成的 Zn-MOF 限制 AuNCs 在水相介质中聚集诱导的增强荧光（AIEE），用于检测 Zn。通过谷胱甘肽还原 Au 合成了谷胱甘肽封端的 AuNCs（GSH-AuNCs）。加入 2-甲基咪唑后，Zn 可以显著增强 GSH-AuNCs 的荧光，这归因于 Zn-MOF 的形成。使用 XRD 和 TEM 对原位形成的 Zn-MOF 进行了表征。通过动态光散射和 TEM 证明了 Zn 诱导的聚集。通过原位形成的 Zn-MOF 诱导聚集后，AuNCs 的量子产率（QYs）达到 36.6%，接近单独 AuNCs 的 9 倍。在此基础上，报道了一种用于检测 Zn 的荧光传感器，其线性范围为 12.3 nM 至 24.6 μM，检测限为 6 nM（S/N = 3）。该传感器成功应用于人血清、牛奶、水和硫酸锌口服液样品中锌含量的测定。本工作提出的新策略可能为金纳米团簇/金属-有机骨架纳米平台在金属离子检测和食品营养评估方面的非常规应用开辟新的研究方向。
