A unique nanogel-based platform for enhanced dual mode tumor MR/CT imaging

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Medical Imaging

Background:

• Dual-modal imaging combining MRI and CT offers complementary diagnostic information.
• Developing effective contrast agents with high performance and safety is crucial for advanced tumor imaging.

Purpose of the Study:

• To create alginate nanogels (AG NGs) co-loaded with gold nanoparticles (AuNPs) and gadolinium (Gd) for enhanced dual-modal MR/CT imaging.
• To evaluate the imaging performance, cellular uptake, and biosafety of these novel nanogels.

Main Methods:

• Synthesized AuNPs and Gd-loaded polyethyleneimine (PEI) nanoparticles, modified with polyethylene glycol (PEG).
• Utilized these nanoparticles as crosslinkers to form hybrid alginate nanogels (AG/PEI-Au-Gd NGs) via a double emulsion process.
• Assessed colloidal stability, cytocompatibility, relaxivity, X-ray attenuation, cellular uptake, and in vitro/in vivo dual-modal imaging capabilities.

Main Results:

• AG/PEI-Au-Gd NGs (83 ± 21 nm) demonstrated excellent colloidal stability and cytocompatibility.
• Achieved higher r1 relaxivity and greater X-ray attenuation compared to control agents.
• Showed enhanced cancer cell uptake and superior dual-modal MR/CT imaging performance in vitro and in vivo tumor models.

Conclusions:

• The developed AG/PEI-Au-Gd NGs are effective dual-modal contrast agents for enhanced tumor imaging.
• These nanogels exhibit improved performance and biosafety, showing potential for clinical translation in MR/CT applications.