Endogenous CO imaging in bacterial pneumonia with a NIR fluorescent probe

Area of Science:

• Biomedical Imaging
• Chemical Biology
• Respiratory Medicine

Background:

• Bacterial pneumonia is a life-threatening respiratory illness requiring rapid and accurate diagnosis.
• Endogenous carbon monoxide (CO) is a key biomarker for bacterial pneumonia.
• Current diagnostic methods may lack the necessary speed and precision.

Purpose of the Study:

• To develop a novel near-infrared (NIR) probe for dual-mode fluorescence and photoacoustic (PA) imaging of endogenous CO.
• To assess the probe's efficacy in detecting CO in bacterial pneumonia models.
• To provide a tool for precise and sensitive diagnosis of bacterial pneumonia.

Main Methods:

• Development of NO2-BODIPY, a CO-reactive NIR probe.
• Evaluation of NO2-BODIPY's response, specificity, and limit of detection (LOD = 20.3 nM).
• Application of the probe for dual-mode imaging in cellular and bacterial pneumonia mouse models, including deep tissue imaging using two-photon excitation.

Main Results:

• NO2-BODIPY demonstrated rapid and specific reaction with CO, generating strong NIR fluorescence and ratiometric PA signals.
• The probe exhibited high sensitivity, high contrast ratio, and a low LOD.
• Successful imaging of endogenous CO in bacterial pneumonia mice with deep tissue penetration was achieved.

Conclusions:

• NO2-BODIPY is a versatile probe for fluorescence/PA dual-mode imaging of endogenous CO.
• The probe offers significant potential for precise and sensitive diagnosis of bacterial pneumonia.
• This dual-mode imaging approach enhances diagnostic capabilities for respiratory illnesses.