Cellular and Intravital Nucleus Imaging by a D-π-A Type of Red-Emitting Two-Photon Fluorescent Probe

Area of Science:

• Biomedical research
• Cellular dynamics
• Fluorescent probe technology

Background:

• Advancements in fluorescent probes are crucial for understanding cellular dynamics in physiological and pathological states.
• Visualizing nuclear morphology and nucleic acid distribution in live cells and in vivo offers critical insights.

Purpose of the Study:

• To introduce Nu-red, a novel two-photon nucleus-imaging fluorescent probe.
• To evaluate the probe's performance for live cell imaging and in vivo applications.

Main Methods:

• Design and synthesis of a donor-π-acceptor rotor probe (Nu-red).
• Characterization of photophysical properties, including excitation/emission wavelengths, quantum yields, and two-photon absorption cross-section.
• Assessment of DNA-binding affinity, cellular uptake, cytotoxicity, and compatibility with other probes.

Main Results:

• Nu-red exhibits long-wavelength excitation/emission, high quantum yields, and excellent two-photon absorption.
• The probe demonstrates high DNA-binding affinity, rapid nuclear entry, low cytotoxicity, and membrane permeability.
• Nu-red successfully visualized cell division, apoptosis, and nuclear changes in a mouse stroke model.

Conclusions:

• Nu-red is a versatile and effective fluorescent probe for nucleus imaging in live cells and in vivo.
• Its properties make it suitable for studying various cellular processes and disease models, including ischemic stroke.