College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China.
College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Aug 5;236:118334. doi: 10.1016/j.saa.2020.118334. Epub 2020 Apr 1.
In the present work, we report a novel chemical approach for the synthesis of orange-red emitting copper nanoclusters (Cu NCs) using L-methionine as stabilizing agent at room temperature for the first time. The synthetic route is facile, economical and viable. The methionine stabilized copper nanoclusters (Cu NCs/Met) were thoroughly characterized by TEM, FT-IR, XPS, UV-Vis, steady state and transient fluorescence spectroscopy. The results show the synthesized Cu NCs/Met with a fluorescence quantum yield of 4.37% possessed high stability and excellent optical features such as large Stokes shift and long fluorescence lifetime (8.3 μs). Significantly, the fluorescence intensity of Cu NCs/Met could be efficiently quenched by norfloxacin (NOR) pharmaceutical. A fast and cost-effective NOR sensor was proposed employing Cu NCs/Met as the fluorescent nanoprobe, and the quenching mechanisms were attributed to inner filter effect and agglomeration-induced quenching. The developed sensor exhibited a high sensitivity and selectivity towards NOR in a wide linear range from 0.05 to 250 μM with a detection limit as low as 17 nM. Moreover, the practicability of the developed NOR sensor for real sample assay was validated with satisfactory recoveries, indicating this sensing platform with great potential for label-free pharmaceutical detection in complex systems.
在本工作中，我们首次报道了一种使用 L-蛋氨酸在室温下合成橙红色发射铜纳米团簇（Cu NCs）的新型化学方法。该合成路线简单、经济且可行。采用 TEM、FT-IR、XPS、UV-Vis、稳态和瞬态荧光光谱对甲硫氨酸稳定的铜纳米团簇（Cu NCs/Met）进行了彻底的表征。结果表明，合成的具有 4.37%荧光量子产率的 Cu NCs/Met 具有高稳定性和出色的光学特性，如大斯托克斯位移和长荧光寿命（8.3 μs）。重要的是，Cu NCs/Met 的荧光强度可以被诺氟沙星（NOR）药物有效地猝灭。我们提出了一种快速且具有成本效益的 NOR 传感器，采用 Cu NCs/Met 作为荧光探针，猝灭机制归因于内滤效应和聚集诱导猝灭。所开发的传感器对 NOR 具有高灵敏度和选择性，在 0.05 至 250 μM 的宽线性范围内检测限低至 17 nM。此外，通过令人满意的回收率验证了所开发的 NOR 传感器用于实际样品分析的实用性，表明该传感平台在复杂体系中用于无标记药物检测具有很大的潜力。
