Iron Oxide Nanoparticles for T1-weighted Magnetic Resonance Imaging: from Rational Design to Clinical Adoption

Abstract: In recent years, the long-term use of gadolinium complexes as T1 contrast agents (CAs) for MRI has attracted increasing attention because of evidence that they remain and may be harmful to the body. Iron oxide nanoparticles (IONPs) have emerged as a promising alternative due to their excellent biocompatibility and tunable magnetic properties. In this perspective, we outline a series of prospective strategies for developing IONP-based T1 CAs: material design (nanoengineering, surface functionalization, and composition control) that governs proton relaxation efficiency; promising stimuli-responsive nanosystems capable of activating diagnostic accuracy by the environment; and the investigation of pharmacokinetic behavior and long-term fate of IONPs for their clinical viability. The key challenge in large-scale production and regulation of innovative IONP-based agents must be overcome for their routine medical applications.