Preparation and Complex Characterisation of Stabilised Gold Nanoparticles: Biodistribution and Application for High...

Area of Science:

• Biomedical Imaging
• Nanotechnology
• Materials Science

Background:

• Micro-computed tomography (µCT) requires effective contrast agents for high-resolution imaging.
• Gold nanoparticles (AuNPs) are promising for biomedical applications due to their unique properties.
• Polyethyleneglycol (PEG)ylation is a common strategy to improve nanoparticle biocompatibility and circulation time.

Purpose of the Study:

• To optimize the Turkevich method for preparing PEG-AuNPs for µCT applications.
• To thoroughly characterize the optimized PEG-AuNPs using multiple analytical techniques.
• To evaluate the performance of PEG-AuNPs as contrast agents in µCT imaging and assess their safety and biodistribution in vivo.

Main Methods:

• Optimization of the Turkevich method for PEG-AuNP synthesis.
• Comprehensive characterization of PEG-AuNPs using independent modalities (e.g., spectroscopy, microscopy).
• In vivo µCT imaging of blood vessels and organs in mice, biodistribution studies, and in vitro cell line experiments (THP-1) to assess NLRP3 inflammasome activation.

Main Results:

• Optimized PEG-AuNPs demonstrated high contrast and sharper µCT imaging compared to a commercial agent.
• PEG-AuNPs exhibited prolonged blood circulation and accumulation in the liver, spleen, and skin.
• No activation of the NLRP3 inflammasome was observed in THP-1 cells, and mice remained healthy over 9 months.
• PEG-AuNPs showed morphological and chemical stability for at least two years under refrigeration.

Conclusions:

• Optimized PEG-AuNPs are effective, safe, and stable contrast agents for high-resolution µCT imaging.
• The prolonged circulation and high contrast provided by PEG-AuNPs enhance the visualization of vasculature and organs.
• PEG-AuNPs represent a promising tool for preclinical imaging studies, with potential for long-term storage and use.