In this work, we demonstrated a facile green method for the preparation of fluorescent copper nanoclusters (Cu NCs) with a high quantum yield of 8.6%, using glutathione as the stabilizing agent and ascorbic acid as the reductant. The as-prepared Cu NCs had good water solubility and ultrafine sizes. Further investigation revealed that the fluorescence of Cu NCs was linearly quenched by nitrite ions over the concentration range of 10–225 μM, with the detection limit of 3.4 μM. The proposed method has been successfully applied to determine nitrite ions in real water samples.

中文翻译：

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高度荧光的谷胱甘肽稳定的铜纳米团簇灵敏和选择性地检测亚硝酸根离子

在这项工作中，我们证明了一种简便的绿色方法，该方法使用谷胱甘肽作为稳定剂和抗坏血酸作为还原剂来制备具有8.6％的高量子产率的荧光铜纳米簇（Cu NCs）。所制备的Cu NCs具有良好的水溶性和超细尺寸。进一步的研究表明，在10–225μM的浓度范围内，亚硝酸根离子可线性淬灭Cu NCs的荧光，检出限为3.4μM。该方法已成功应用于实际水样中亚硝酸根离子的测定。