Going Below and Beyond the Surface: Microneedle Structure, Materials, Drugs, Fabrication, and Applications for Wound Healing and Tissue Regeneration

Microneedles, a novel drug delivery system, have gained attention for their non-invasive, painless, and controllable drug delivery capabilities. Initially designed for transdermal drug delivery, they are now being used to promote wound healing and tissue regeneration with promising results. This review covers the potential cargos, structural designs, material selection, and drug release mechanisms of microneedles, as well as various fabrication methods and their pros and cons. It also summarizes recent advancements in microneedle-assisted healing and regeneration across various tissues, including skin, cardiac, bone, tendon, ocular, vascular, oral, hair, spinal cord, and uterine tissues, providing a guideline for designing effective microneedle systems.