Dual imaging agent for magnetic particle imaging and computed tomography

Area of Science:

• Biomedical Engineering
• Materials Science
• Nanotechnology

Background:

• Magnetic particle imaging (MPI) offers high sensitivity for tracking superparamagnetic iron oxide nanoparticle (SPION) tracers but lacks anatomical information.
• Computed tomography (CT) provides high-resolution anatomical detail but has limitations in sensitivity for certain applications.
• A multimodal imaging agent combining MPI and CT capabilities is desirable for enhanced diagnostic power.

Purpose of the Study:

• To develop and characterize a novel dual-imaging agent capable of simultaneous MPI and CT imaging.
• To evaluate the performance of the dual-imaging agent in terms of MPI sensitivity, resolution, and CT contrast.
• To assess the potential of the dual-imaging agent for advanced imaging techniques like dual-energy CT (DECT).

Main Methods:

• Fabrication of composite nanoparticles containing both SPIONs and hafnium oxide (hafnia) using flash nanoprecipitation.
• Characterization of nanoparticle composition and structure using transmission electron microscopy and elemental mapping.
• Evaluation of magnetic properties, MPI performance (sensitivity and resolution), and CT contrast in preclinical and clinical scanners.

Main Results:

• Successfully synthesized dual-imaging MPI/CT agents with co-encapsulated iron oxide and hafnia.
• The dual-imaging agent demonstrated approximately 3x better MPI sensitivity compared to a commercial tracer.
• Enhanced CT contrast was observed compared to iodine-based agents, with potential for DECT applications and virtual monochromatic imaging.

Conclusions:

• The developed dual-imaging agent successfully integrates MPI and CT contrast functionalities.
• The agent exhibits improved MPI sensitivity and superior CT contrast, offering advantages over existing agents.
• This novel agent holds promise for advanced multimodal biomedical imaging, particularly with DECT techniques.