Mobile Phone Flashlight-Excited Red Afterglow Bioimaging

Area of Science:

• Materials Science
• Biomedical Imaging
• Organic Chemistry

Background:

• Organic room temperature phosphorescence (RTP) materials offer advantages in bioimaging due to their long lifetimes, enabling background noise reduction.
• Current RTP materials often require harmful ultraviolet (UV) excitation and produce green/yellow emissions with limited tissue penetration, hindering in vivo applications.
• There is a need for safer and more effective RTP materials for clinical diagnosis and pathological studies.

Purpose of the Study:

• To develop novel organic luminogens excitable by safe light sources like sunlight and mobile phone flashlights.
• To achieve bright red RTP emission with ultralong lifetimes for enhanced bioimaging capabilities.
• To demonstrate the feasibility of mobile phone flashlight-excited in vivo bioimaging for preclinical applications.

Main Methods:

• Design and synthesis of organic luminogens utilizing various electronic pull-push systems.
• Optimization of molecular geometry and electronic properties to achieve specific emission colors and lifetimes.
• In vivo imaging experiments on living mice using mobile phone flashlight excitation.

Main Results:

• Successfully developed organic luminogens excitable by sunlight and mobile phone flashlights.
• Achieved bright red RTP emission with an impressive lifetime of up to 344 ms.
• Demonstrated the first-ever mobile phone flashlight-excited red afterglow imaging of lymph nodes in living mice.
• The developed method provides deep tissue penetration and high signal-to-noise ratios for in vivo imaging.

Conclusions:

• Novel organic RTP materials offer a safe and efficient alternative to traditional UV-excited probes.
• The use of sunlight or mobile phone flashlights as excitation sources makes bioimaging more accessible and safer.
• This technology opens new avenues for in vivo bioimaging, particularly for lymph node visualization in preclinical studies.