Therapeutic advances of magnetic nanomaterials in chronic wound healing

Millions of patients worldwide suffer from chronic and non-healing wounds, leading to hospitalizations, infections, and even fatalities. Despite advances in clinical therapies, wound management remains a significant challenge due to the complex wound environment and increasing antibiotic resistance. Consequently, there is an urgent need for innovative strategies to address chronic wound treatment. Among the emerging approaches, nanomaterial-based therapeutic systems, especially magnetically responsive strategies, are gaining considerable attention. Upon exposure to an external magnetic field, magnetic nanomaterials (MNMs) can induce electromagnetic, magnetothermal, and magnetomechanical effects at the wound site. Additionally, compared with other exogenous stimuli-responsive therapies, magnetic fields offer distinct advantages, including noninvasiveness, deep tissue penetration, and high sensitivity for remote control and actuation of cells. In this review, we first outline the fundamental properties, design strategies, and biological mechanisms of MNMs and discuss their various applications in chronic wound therapy, such as antibacterial effects, magnetothermal therapy, controlled drug delivery, mechanical cell manipulation, wireless electrical stimulation, and dualstimulation approaches. We then highlight recent advancements in MNMs for wound monitoring and management, including magnetic nanorobots and "smart dressings". Finally, we offer our insights on the current challenges of MNMs and propose future directions to enhance their clinical translation. Overall, this review emphasizes the potential of magnetic nanomaterial-based therapeutic systems to transform the landscape of chronic wound management.