College of Food Science and Engineering, Shandong Agricultural University, Taian, 271018, Shandong, People's Republic of China.
College of Chemistry and Material Science, Shandong Agricultural University, Taian, 271018, Shandong, People's Republic of China.
Mikrochim Acta. 2020 Sep 1;187(9):534. doi: 10.1007/s00604-020-04508-z.
Carbon dots and gold nanoclusters co-encapsulated by zeolitic imidazolate framework-8 (CDs/AuNCs@ZIF-8) have been obtained at room temperature. The composite has been applied to the ratiometric fluorescence determination of mercury(II). The composite shows fluorescence emission maxima at 440 and 640 nm under 360 nm excitation, due to the CDs and AuNCs, respectively (associated quantum yields were 18% and 17%, respectively). In the presence of Hg, the fluorescence at about 640 nm is quenched, while the fluorescence at about 440 nm is unaffected. The CDs/AuNCs@ZIF-8 composite allows the sensitive detection of Hg, with the fluorescence intensity ratio (I/I) decreasing linearly with Hg concentration over the range 3-30 nM. The fluorescence emission of the composite changes color from red to blue with increasing Hg under UV excitation, which can easily be discerned visually. This visual detection of Hg is due to the high fluorescence quantum yields of the CDs and AuNCs and the ~ 200 nm separation between the two emission maxima. Graphical abstract (A) Schematic diagram showing the operating principle of the determination for Hg(II). (B) Digital graph of the solutions in absence and presence of 30 nM Hg(II) under a portable UV lamp.
在室温下合成了沸石咪唑酯骨架-8（ZIF-8）共包封的碳点和金纳米团簇（CDs/AuNCs@ZIF-8）。该复合材料已应用于汞（II）的比率荧光测定。由于 CDs 和 AuNCs，该复合材料在 360nm 激发下分别显示出 440nm 和 640nm 的荧光发射最大值（相应的量子产率分别为 18%和 17%）。在存在 Hg 的情况下，约 640nm 的荧光被猝灭，而约 440nm 的荧光不受影响。CDs/AuNCs@ZIF-8 复合材料允许对 Hg 进行灵敏检测，荧光强度比（I/I）随 Hg 浓度在 3-30nM 范围内线性降低。在 UV 激发下，随着 Hg 的增加，复合材料的荧光发射从红色变为蓝色，肉眼可轻松识别。这种对 Hg 的可视化检测归因于 CDs 和 AuNCs 的高荧光量子产率以及两个发射最大值之间约 200nm 的分离。
