State Key Laboratory of Fine Chemicals, School of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin, Liaoning 124221, People's Republic of China.
Methods Appl Fluoresc. 2018 Jun 28;6(3):035015. doi: 10.1088/2050-6120/aac8f5.
Water-soluble and ultra-stable L-proline-protected copper nanoclusters (Cu NCs) are reported, which overcome the bottleneck that Cu NCs are easily oxidized. The average size of Cu NCs is found to be 1.88 ± 0.17 nm. The as-prepared Cu NCs exhibit an excellent stability over the physiologically relevant pH range, long storage time, high ionic strength, high concentration of hydrogen peroxide and various common metal ions. The fluorescence intensity of Cu NCs maintains no change after 5 months stored in the refrigerator. Interestingly, the Cu NCs show a pH-dependent fluorescence behavior between 9 and 13, and the reversible process can be repeated for 8 consecutive cycles with the excellent reversibility of the fluorescence intensity. Moreover, the as-prepared Cu NCs display the solvent-dependent properties in the dimethyl sulfoxide and ethylenediamine, where the emission color turn to be green and yellow from blue, respectively. This unique fluorescence property of Cu NCs will make them serve as good probes in analytical applications.
水溶性和超稳定的 L-脯氨酸保护的铜纳米簇（Cu NCs）被报道，克服了 Cu NCs 容易氧化的瓶颈。发现 Cu NCs 的平均尺寸为 1.88±0.17nm。所制备的 Cu NCs 在生理相关的 pH 范围内表现出优异的稳定性，长时间储存、高离子强度、高浓度的过氧化氢和各种常见金属离子。Cu NCs 在冰箱中储存 5 个月后，荧光强度保持不变。有趣的是，Cu NCs 在 9 到 13 之间表现出 pH 依赖性荧光行为，并且荧光强度的可逆过程可以重复 8 个连续循环，具有优异的可逆性。此外，所制备的 Cu NCs 在二甲基亚砜和乙二胺中表现出溶剂依赖性性质，其中发射颜色分别从蓝色变为绿色和黄色。Cu NCs 的这种独特荧光性质将使它们在分析应用中成为良好的探针。
