Recently, a research team led by Professor Qilong Wang from the Affiliated Huai’an No. 1 People’s Hospital of Nanjing Medical University (NMU) (also known as Huai’an First People’s Hospital) published a significant research article entitled Design of a NIR-I Viscosity-Sensitive Fluorescent Probe for Tracking Nuclear Physiological Changes During Different Cell Cycle Stages in Analytical Chemistry, a leading international journal published by the American Chemical Society (ACS) and ranked as a Top (Q1) journal by the Chinese Academy of Sciences. The study was selected as the cover article of the issue.
Professor Qilong Wang, Researcher Chao Luo, and Associate Researcher Li Zhang serves as co-corresponding authors, and Dr. Jiaying Yu, a young PhD researcher, is the first author.
Figure 1. This study was selected as the cover article of Analytical Chemistry.
Research Overview
This study proposes a non-conventional design strategy for a viscosity-sensitive fluorescent probe. By leveraging multiple intermolecular interactions, including electrostatic attraction, π–π stacking, and weak hydrogen bonding, the probe binds to grooves adjacent to DNA base pairs. Structural modulation of the molecular rotor alters electron cloud migration and excited-state behavior during probe photoexcitation, thereby suppressing intramolecular charge transfer and activating the fluorescence signal.
Figure 2. (A) Fluorescence emission mechanism of the viscosity-sensitive probe YY-2; (B) spatiotemporal imaging of cells during mitosis; (C) spatiotemporal imaging of the nucleus, cytoplasm, and apoptotic bodies during apoptosis.
Conventional nuclear probes often suffer from limitations such as short emission wavelengths, complex operational procedures, single functionality, and an inability to simultaneously recognize other subcellular organelles. As research into cellular life processes continues to deepen, increasing demands have emerged for the spatiotemporal monitoring of subcellular structures and intracellular physical microenvironments. In this context, the development of a multifunctional NIR-I nuclear imaging probe is of great significance.
The viscosity-sensitive probe YY-2 exhibits distinct fluorescence intensities across multiple subcellular organelles, enabling effective differentiation of the nucleolus, chromosomes, nuclear membrane, and cytoplasm. Further studies revealed that the nucleolus possesses relatively high viscosity, a characteristic closely related to key cellular processes such as cell proliferation and division. With its excellent performance, the YY-2 probe enables “live broadcast” visualization of cellular life processes. Using this probe, researchers achieved dynamic monitoring of changes in nuclear morphology and viscosity during cell division and apoptosis, and observed phenomena such as the formation of multinucleated cells caused by abnormal cytoplasmic division.
This study offers new insights into the rational design of novel NIR fluorescent probes and their applications in live-cell dynamic imaging, and provides a new technical approach for studying nucleus-associated cellular life processes.
Original article: https://pubs.acs.org/doi/10.1021/acs.analchem.5c05382
(Drafted by Professor Qilong Wang’s research team, Chao Luo and Jiaying Yu; Translation revised by Bei Zhang)
