Recent Advances of Magnetic Nanomaterials for Bioimaging, Drug Delivery, and Cell Therapy

Magnetic nanoparticles (MNPs) are gaining much attention due to their applications in specialized fields, including diagnosis, bioimaging, drug delivery, and cell therapy. In recent years, the field of stem cell and regenerative medicine comprising tissue engineering and drug delivery has been powered by nanoparticles. Particularly, mesenchymal stem cells (MSCs) are characterized with adequate immunomodulatory potential coupled with an excellent regenerative ability that contributes to improved therapy of various diseases. For clinical applications of MSCs, tracking and labeling are crucial to determine cell homing and distribution. Therefore, due to the high potential of MNPs in stem cell therapy, this review comprehensively uncovers the advancements in the respective field. Also, it discusses the usage of surface-functionalized materials in improving the physicochemical properties of MNPs, making them suitable candidates for several biomedical applications. Moreover, we have discussed that these nanoparticles within applied magnetic field and electromagnetic field have been considered multifunctional agents for labeling, stimulating, tracking, and targeting stem cells in vitro and in vivo. Additionally, the discussion comprises the progress and challenges associated with MNPs used as effective therapeutic, delivery, and diagnostic agents to treat cancer, cardiovascular, neurodegenerative, and bone-related disorders. Finally, the review discussed that the magnetic nanoparticles have also been widely used for targeted cancer cell therapy due to mechanical force for killing cancer cells under a magnetic field. It is concluded that the mechanical force produced by MNPs in a low-frequency vibrating magnetic field is the most promising and safe option for the destruction of tumor cells. In short, this review summarized the role of magnetic nanomaterials for effective, safe, and efficient nanomaterial-cell-based therapies.