Sensitive and high resolution subcutaneous fluorescence in vivo imaging using upconversion nanoparticles and...

Area of Science:

• Biomedical Optics
• Nanotechnology
• Medical Imaging

Background:

• Upconversion nanoparticles (UNPs) offer unique optical properties for bioimaging.
• Autofluorescence from biological tissues can interfere with conventional imaging techniques.
• High-resolution in vivo imaging is crucial for preclinical research and disease detection.

Purpose of the Study:

• To develop a sensitive and high-resolution small animal in vivo imaging system.
• To evaluate the performance of upconversion nanoparticles (UNPs) in fluorescence tomography.
• To assess the potential of UNP microarrays for subcutaneous disease detection.

Main Methods:

• Development of a fluorescence tomography system utilizing upconversion nanoparticles (UNPs).
• Theoretical explanation of UNP fluorescence tomography precision using finite element method (FEM).
• Preparation and subcutaneous implantation of UNP fluorophore microarrays in mouse models.
• Application of an optical clearing method to enhance skin transparency and imaging resolution.

Main Results:

• The UNP-based system achieved higher precision in fluorescence tomography compared to ordinary fluorophores.
• A high subcutaneous detection sensitivity of 0.93 × 10(-4) wt% was achieved in tissue phantoms due to UNPs' autofluorescence-insensitivity.
• Optimized system demonstrated a spatial resolution of 50 μm for in vivo detection of subcutaneous UNP microarrays.

Conclusions:

• The developed system and UNP microarrays enable sensitive and high-resolution subcutaneous in vivo detection.
• This technology holds significant potential for high-throughput detection of tumors and other diseases.
• UNPs provide a promising platform for advanced biomedical imaging applications.