Optoacoustic imaging enabled biodistribution study of cationic polymeric biodegradable nanoparticles

Area of Science:

• Biomedical Engineering
• Materials Science
• Nanotechnology

Background:

• Solid nanoparticles for molecular imaging face toxicity challenges.
• Near-infrared (NIR) dyes have limitations like poor stability and rapid clearance.
• NIR dye-loaded nanoparticles offer a potential solution to overcome these drawbacks.

Purpose of the Study:

• To develop and evaluate novel cationic nanoparticles loaded with NIR dyes for molecular imaging.
• To investigate the in vivo biodistribution of these nanoparticles using multispectral optoacoustic tomography (MSOT).
• To assess the potential of these nanoparticles as contrast agents for diagnostic and theranostic applications.

Main Methods:

• Synthesis of cationic nanoparticles using poly(D,L-lactide-co-glycolic acid) (PLGA) and polyethyleneimine (PEI).
• Characterization of nanoparticle colloidal stability and optical properties.
• In vivo biodistribution studies using MSOT after intravenous, intraperitoneal, and subcutaneous administration.

Main Results:

• The prepared PEI-PLGA nanoparticles demonstrated good colloidal stability and suitable optical properties for MSOT.
• In vivo biodistribution assays revealed significant accumulation and retention in the liver and spleen for at least 24 hours.
• The nanoparticles generated high optoacoustic signals with sharp spectral characteristics.

Conclusions:

• Cationic PEI-PLGA nanoparticles loaded with NIR dyes are a promising alternative to solid nanoparticles and free NIR dyes for molecular imaging.
• These nanoparticles exhibit favorable biodistribution profiles and stability for in vivo applications.
• Their properties make them suitable for MSOT and potential candidates for theranostic strategies.