Highly Loaded Semipermeable Nanocapsules for Magnetic Resonance Imaging

Area of Science:

• Biomedical Engineering
• Materials Science
• Radiology

Background:

• Magnetic resonance imaging (MRI) is crucial for medical diagnostics.
• Effective contrast agents are needed for enhanced MRI visualization.
• Key challenges include contrast enhancement, low toxicity, and controlled biodistribution.

Purpose of the Study:

• To develop novel polyurea nanocapsules for improved MRI contrast agents.
• To investigate the relationship between nanocapsule crystallinity and relaxivity.
• To evaluate the biodistribution and cellular uptake of the developed nanocarriers.

Main Methods:

• Synthesis of polyurea nanocapsules encapsulating the gadolinium complex Gadobutrol.
• Characterization of nanocapsule crystallinity and relaxivity.
• In vitro cellular identification and in vivo biodistribution studies post-injection.

Main Results:

• Aliphatic polyurea nanocapsules exhibited higher crystallinity and relaxivity (up to 40 s⁻¹ mmol⁻¹ L) compared to aromatic ones.
• High local concentration of Gadobutrol within nanocapsules was achieved.
• Nanocapsules were identified in cells and primarily localized in the liver and spleen after injection.

Conclusions:

• Polyurea nanocapsules effectively encapsulate Gadobutrol, enhancing MRI contrast.
• Nanocapsule properties, such as crystallinity, influence relaxivity.
• The targeted biodistribution in the liver and spleen facilitates significant contrast enhancement in MRI.