Herein, a simple, green and low-cost method was established to synthesize l-proline-stabilized copper nanoclusters (l-Pro-Cu NCs) with good water solubility, excellent photostability and resistance to sodium chloride. A series of methods including fluorescence spectroscopy, UV–Vis absorption spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy were used to characterize the structure and optical performance of the Cu NCs. The as-prepared Cu NCs showed green fluorescence with the excitation wavelength of 373 nm. Under the optimal detection conditions, an excellent linear relationship was observed between relative fluorescence intensity (F₀/F) and the concentrations of quercetin ranging from 0.5 to 50 μM, and the detection limit (LOD) was 0.012 μM. Moreover, the proposed method provided an excellent platform for the detection of quercetin in the real samples.

中文翻译：

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一锅绿色合成l-脯氨酸稳定的铜纳米簇用于槲皮素传感

本文中，建立了一种简单，绿色且低成本的方法来合成具有良好的水溶性，优异的光稳定性和耐氯化钠性能的l-脯氨酸稳定的铜纳米团簇（l -Pro-Cu NCs）。一系列方法包括荧光光谱法，UV-Vis吸收光谱法，傅立叶变换红外光谱法，透射电子显微镜法和X射线光电子能谱法用于表征Cu NCs的结构和光学性能。所制备的Cu NCs显示绿色荧光，激发波长为373 nm。在最佳检测条件下，相对荧光强度（F ₀ / F）槲皮素的浓度范围为0.5至50μM，检出限（LOD）为0.012μM。而且，该方法为实际样品中槲皮素的检测提供了一个极好的平台。