Metal-free and MRI visible theranostic lyotropic liquid crystal nitroxide-based nanoparticles

Area of Science:

• Biomedical Engineering
• Materials Science
• Nanotechnology

Background:

• Developing clinically viable nanomaterials for MRI contrast agents is crucial for translatable theranostic applications.
• Existing agents often rely on heavy metals, raising toxicity concerns.
• There is a need for improved, low-toxicity MRI contrast agents.

Purpose of the Study:

• To synthesize and characterize novel lyotropic liquid crystal nanoparticles loaded with paramagnetic nitroxide lipids for MRI contrast enhancement.
• To evaluate the in vitro and in vivo safety and efficacy of these metal-free nanoparticles as liver MRI contrast agents.

Main Methods:

• Nanoparticles were synthesized by loading lyotropic liquid crystals with paramagnetic nitroxide lipids.
• In vitro cytotoxicity screening was performed.
• Maximum tolerated dose was determined in rats.
• Pharmacokinetic profiles were established following intravenous administration in rats.
• In vivo liver MRI performance was assessed.

Main Results:

• The synthesized nanoparticles exhibited enhanced proton relaxivities comparable to clinical gadolinium-based agents.
• These nanoparticles demonstrated low toxicity, high water solubility, and excellent colloidal stability.
• In vivo studies confirmed good tolerability and effective liver MRI contrast enhancement.
• The agents were proven to be effective liver MRI contrast agents without using heavy metals.

Conclusions:

• Lyotropic liquid crystal nanoparticles loaded with nitroxide lipids represent a promising class of metal-free MRI contrast agents.
• These nanoparticles offer a biocompatible, stable, and effective alternative to traditional heavy metal-based agents.
• The developed agent shows potential for translatable theranostic applications, particularly in liver imaging.