Live Cell Imaging Using Photoswitchable Diarylethene-Doped Fluorescent Polymer Dots

Area of Science:

• Nanomaterials Science
• Biomedical Imaging
• Photochemistry

Background:

• Fluorescence photoswitching with nanomaterials offers potential for biological target imaging.
• Real-time microscopy of biological targets using photoswitchable nanoparticles remains a significant challenge.
• Overcoming limitations in current photoswitchable nanoparticle technology is crucial for advancing live-cell imaging.

Purpose of the Study:

• To develop advanced photoswitchable fluorescent nanoparticles for practical, real-time live-cell imaging.
• To enhance the photoswitching properties of nanoparticles for prolonged "off-state" durations.
• To demonstrate the utility of these novel nanoparticles in cellular imaging applications.

Main Methods:

• Development of photoswitchable fluorescent diarylethene-doped polymer nanoparticles (P-dots).
• Utilizing Xe lamp irradiation and a green fluorescent protein filter cube for photoswitching.
• Implementing live macrophage cell imaging and single particle imaging techniques.

Main Results:

• Achieved a 34-times prolonged "off-state" in P-dots doped with a diarylethene-containing methoxy substituent.
• Observed an 11-times slower recovery of fluorescence from the "off-state" to the "on-state" in cellular imaging.
• Successfully demonstrated practical imaging of lysosomes within macrophage cells.

Conclusions:

• The developed diarylethene-doped P-dots exhibit significantly improved photoswitching capabilities.
• These P-dots show great potential for advanced cellular imaging and microscopy applications.
• The enhanced "off-state" duration and slower recovery are key advantages for real-time biological imaging.