Fabrication and Applications of Magnetic Nanoparticles-Based Drug Delivery System: Challenges and Perspectives

Engineered magnetic nanoparticles (MNPs) have aroused great interest due to their excellent physicochemical properties such as optic, electronic, and especially magnetics, which could be in combination with the nano-size effect favorable for biomedical applications. Recently, MNPs as multifunctional nanoplatforms have opened a new avenue for simultaneous therapeutic systems and magnetic resonance imaging (MRI) monitoring systems. In particular, the use of the external magnetic field could enhance the penetration into the hypoxic tumor regions overcoming the inefficiency of conventional cancer therapeutic methods. Among the versatile MNPs-based nanocarriers, iron oxides mainly consisted of superparamagnetic maghemite (γ-Fe2O3) and magnetite (Fe3O4) nanoparticles with a size of 10–100 nm have been widely utilized owing to the good biocompatibility and feasible surface modification by organic and/or inorganic agents for drug loading. In this chapter, we discuss the role of size, surface, and shape (3S) in influencing the in vitro cellular uptake and in vivo biodistribution behaviors and focus on the current challenges regarding the translational of MNPs in clinics aiming at optimizing the system for effective drug transportation. New perspectives are also put forward to outline the future development tendency of MNPs-based drug delivery system.