A novel colorimetric/fluorescent dual-signal probe based on silver nanoparticles functionalized with L-cysteine and rhodamine 6G derivatives for copper ion detection and cell imaging

• Published in: Environmental research 2023-11, Vol.236 (Pt 1), p.116540-116540, Article 116540
• Main Authors: Lu, Mingrong, Zhang, Yao, Li, Shaoqing, Zhang, Yifei, Fang, Shuju, Yang, Wenrong, Yang, Min, Wang, Hongbin
• Format: Article
• Language: English
• Subjects: Cell imaging; Copper ion; Dual-signal probe; L-cysteine; Rhodamine 6G derivatives; Silver nanoparticles
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2023.116540

The dual-signal probe utilizing functionalized silver nanoparticles (AgNPs) is a promising sensing tool. Herein, a novel colorimetric/fluorescent dual-signal probe (AgNPs-L-Cys-Rh6G2) was fabricated for copper ion (Cu2+) detection and cell imaging by using L-cysteine as a “bridge” to connect AgNPs and rhodamine 6G derivatives. The AgNPs-L-Cys-Rh6G2 probe exhibits a dual-signal response to Cu2+ due to Rh6G2 hydrolysis, resulting in a high fluorescence response and a significant change in color from light yellow to pink under sunlight. The linear detection ranges of the AgNPs-L-Cys-Rh6G2 probe for Cu2+ were 100–450 μM and 150–650 μM using fluorescent and colorimetry methods, respectively. The detection limits were as low as 0.169 μM and 1.36 μM, respectively. Meanwhile, the proposed probe was applied to detect Cu2+ in the actual sediment with satisfactory recovery and low relative standard deviation. Furthermore, the probe was further employed for fluorescence imaging in HeLa cells. In brief, the developed AgNPs-L-Cys-Rh6G2 sensing platform can be used for simultaneous Cu2+ determination and cell imaging. [Display omitted] •A novel fluorescent and colorimetric dual-signal probe were obtained by functionalizing AgNPs with L-Cys and Rh6G2.•The dual-signal response is induced by the opening of the spirolactam ring caused by the catalytic hydrolysis of Cu2+.•The probe is not only highly selective for Cu2+, but also suitable for practical sediment and cell imaging.