Magnetic Micro/Nano Carriers for Targeted and Sustained Drug Delivery Systems

ABSTRACT

This review provides a comprehensive overview of magnetic micro‐ and nano‐carrier systems for targeted and sustained drug delivery, highlighting recent advancements in formulation design, synthesis parameters, and multi‐stimuli‐responsive mechanisms to overcome conventional chemotherapy limitations. Unlike existing literature, this work uniquely synthesizes the structural and functional trade‐offs across magnetic nanoparticles, liposomes, and microspheres while critically evaluating translation‐defining synthesis parameters. Conventional chemotherapy often lacks selectivity, leading to adverse systemic effects; targeted and sustained magnetic drug delivery (MDD) uses external magnetic field gradients to guide biocompatible carriers to pathological sites. These platforms enhance therapeutic efficacy, reduce systemic toxicity, cross complex biological barriers like the blood–brain barrier, and provide controlled release. The review explores carrier design, surface functionalization, and synthesis optimization. However, key translational challenges persist, including severe batch‐to‐batch variability during scale‐up, rapid reticuloendothelial clearance due to in vivo protein corona formation, limited magnetic field penetration in deep‐tissue human anatomy, and an ambiguous regulatory landscape. Finally, we outline critical future directions, focusing on image‐guided theranostics, non‐invasive robotic endoscopic navigation, standardized characterization protocols, and biocompatible/biodegradable platforms to accelerate clinical adoption in oncology and neurology.