The bright fluorescence of non-aromatic molecules in aqueous solution originates from pH-induced CTE behavior

Non-aromatic fluorescent materials with inherent visible light emission have received widespread atten-tion. In this work, a biomimetic fluorescent molecule CA-AEP with a dipeptide structure is introduced. CA-AEP will emit bright biomimetic fluorescence in aqueous solutions by adjusting the pH, which has never been reported. This unique luminescent characteristic can be rationalized by the clustering-triggered emission (CTE) mechanism. In addition, CA-AEP can be used to monitor the maximum dynamic pH in the alkaline range of aqueous systems. Finally, the cytotoxicity assay to A549 cells showed that CA-AEP was non-toxic. Therefore, this work provides a new type of luminogen, which has potential applica-tion prospects in the field of environmental monitoring and cell biology. ? 2021 Elsevier B.V. All rights reserved.

Automated summary

This study introduces a biomimetic fluorescent molecule CA-AEP with a dipeptide structure that emits bright biomimetic fluorescence in aqueous solutions by adjusting the pH, a characteristic explained by the clustering-triggered emission (CTE) mechanism. CA-AEP can also be used to monitor the maximum dynamic pH in alkaline aqueous systems, and cytotoxicity assays show it is non-toxic to A549 cells. This work provides a new type of luminogen with potential applications in environmental monitoring and cell biology.