One-step synthesis and applications of fluorescent Cu nanoclusters stabilized by l-cysteine in aqueous solution

• A novel, one-step strategy for synthesizing water-soluble CuNCs was established.
• A simple, selective, and cost-effective assay for Hg2+ was developed.
• CuNCs may broaden ways for fluorescent staining and coding.

Herein, an innovative and simple strategy for synthesizing high fluorescent Cu nanoclusters was successfully established while l-cysteine played a role as the stabilizer. Meaningfully, the current Cu nanoclusters together with a quantum yield of 14.3% were prepared in aqueous solution, indicating their extensive applications. Subsequently, the possible fluorescence mechanism was elucidated by fluorescence, UV–vis, HR-TEM, FTIR, XPS, and MS. Additionally, the CuNCs were employed for assaying Hg2+ on the basis of the interactions between Hg2+ and l-cysteine; thus facilitating the quenching of their fluorescence. The proposed analytical strategy permitted detections of Hg2+ in a linear range of 1.0 × 10−7 mol L−1 × 10−3 mol L−1, with a detection limit of 2.4 × 10−8 mol L−1 at a signal-to-noise ratio of 3. Significantly, this CuNCs described here were further applied for coding and fluorescent staining, suggesting may broaden avenues toward diverse applications.

An innovative and simple strategy for synthesizing high-fluorescent Cu nanoclusters stabilized with l-cysteine has been successfully established in aqueous solution. Significantly, the Cu nanoclusters were employed for sensitive and selective detections of Hg2+, coding and fluorescent staining, suggesting their potential toward various applications.Figure optionsDownload as PowerPoint slide