Achieving Near-Infrared Organic Room-Temperature Phosphorescence for High-Resolution Immune Response Monitoring and...

Area of Science:

• Materials Science
• Biomedical Engineering
• Organic Chemistry

Background:

• Organic near-infrared (NIR) room-temperature phosphorescent (RTP) materials offer advantages for bioimaging by reducing background noise and tissue autofluorescence.
• Developing stable and efficient NIR RTP materials is crucial for high-contrast in vivo imaging applications.

Purpose of the Study:

• To synthesize novel octa-ring fused RTP molecules with B─N coordination bonds for NIR emission.
• To fabricate stable, bright nanoparticles for enhanced bioimaging.
• To develop a specific and quantitative nanoprobe for monitoring tumor immune response.

Main Methods:

• Synthesis of octa-ring fused RTP molecules (TPP-BN and TPP-BF) via a two-step reaction.
• Fabrication of PMMA-b-PEG based nanoparticles (PNPs) using PMMA-b-PEG as host and surfactant.
• Development of a granzyme B (GrB)-responsive nanoprobe (Q-BFNP).

Main Results:

• Achieved NIR phosphorescent emission at 819 nm with a 28.6 ms lifetime.
• PNPs exhibited a five-fold brighter afterglow compared to conventional F127-based nanoparticles (FNPs).
• In vivo studies showed high signal-to-background ratios (SBR) up to 216.4 for tumor immune response monitoring.

Conclusions:

• A new method for constructing NIR organic RTP probes was established.
• The developed RTP materials and nanoprobe show significant potential for real-time, high-contrast bioimaging.
• Advancement in applications of RTP materials for precise tumor immune monitoring was demonstrated.