Photoluminescent Ag nanoclusters for reversible temperature and pH nanosenors in aqueous solution
A facile, straightforward, and green method was reported for the preparation of water-soluble and highly luminescent silver nanoclusters (AgNCs) using captopril (Capt) as a stabilizing agent. The as-prepared Capt@AgNCs exhibited bright red emission with a strong peak centered at 637 nm and showed low toxicity and good stability. Interestingly, the AgNCs displayed temperature sensitivity based on obvious temperature dependence of the fluorescence emission intensity. Furthermore, the AgNCs showed a good reversible and linear response to the environment temperature over the range from 10 °C to 45 °C with a high resolution and activation energy, which allowed its potential application as a fluorescent nanothermometer. In addition, the AgNCs were prepared to monitor pH via the fluorescence intensity of AgNCs responding sensitively to pH fluctuating within a wide range from 2.08 to 6.06. The study provides promising applications as a convenient and eco-friendly fluorescent temperature and pH nanosenser in environmental and biological fields.
KeywordsFluorescence Silver nanoclusters Temperature nanosensors pH nanosensors
This work was supported by the National Natural Science Foundation of China (No. 21475080, No. 21571116, and No. 21575084), Program for the Top Young and Middle-aged Innovative Talents of Higher Learning Institutions of Shanxi Province (OIT), Shanxi Province Hundred Talent Project, the Youth Science Foundation of Shanxi Province (No.201701D221029) and Primary Research and Development Plan of Shanxi Province (No. 201703D321031).
Compliance with ethical standards
The study was performed in accordance with the ethical standards.
Conflict of interest
The authors declare that they have no conflict of interest.
The HeLa cells were donated by Tongpai Biological Cell Bank (Shanghai, China). The study is therefore exempt from institutional review board (IRB) approval.
This research did not involve human participants or animals, and therefore, obtaining informed consent was not required.
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