Discovery of a near-infrared fluorescent probe for G-quadruplexes by exploiting the concept of unfolding-intramolecular-aggregation-induced emission

• Published in: Bioorganic chemistry 2024-02, Vol.143, p.107006-107006, Article 107006
• Main Authors: Wang, Xiao-Dong, Liu, Yong-Si, Hu, Ming-Hao
• Format: Article
• Language: English
• Subjects: Fluorescent Dyes - chemistry; Fluorescent probe; G-quadruplex; G-Quadruplexes; Intramolecular aggregation; Near-infrared; Self-folding
• ISSN: 0045-2068; 1090-2120
• DOI: 10.1016/j.bioorg.2023.107006

[Display omitted] •A design strategy for developing promising DIE G4 fluorescent probes was raised.•A self-folded, NIR probe for selectively illuminating G4s was engineered.•G4s triggered the probe fluorescence by unfolding its intramolecular aggregation (UIA). In the very recent years, the concept of disaggregation-induced emission (DIE) has been applied to design G4 probes, thereby rendering several fluorophores that may suffer from aggregation-induced quenching (ACQ) to develop into desirable G4-selective probes. However, the design idea based on DIE was often limited by the instability and irreversibility of the “intermolecular” aggregation/disaggregation process. In this study, a self-folded, near-infrared fluorescent probe for selectively illuminating G4s was engineered. This probe restored its fluorescence via unfolding of its intramolecular aggregation (UIA) mediated by distinctive G4 binding, which may display more controllable background emission as well as more promising ability to track G4 forming dynamics as compared to the reported DIE probes. Altogether, this study provided insights into the development of new types of applicable G4 selective fluorescent probes.