External physical field-responsive nanocomposite hydrogels for wound healing applications

Hydrogels, as hydrophilic polymers with intricate 3D network structures, exhibit remarkable properties such as adhesion and moisture retention, promising broad applications in wound healing. However, the functionality of a single-component hydrogel system remains relatively simplistic, hindering the advancement towards the spatially and temporally controllable functionality of wound dressings. The incorporation of external physical field-responsive nanomaterials (EPFR-NMs) as composite components offers a viable pathway to modify hydrogels, and the strategies of integrating nanoparticles with hydrogels to create functional external physical field-responsive nanocomposite hydrogels (EPFR-NHs) have garnered significant interest among researchers. In this review, we comprehensively summarize the classification and acting mechanisms of EPFR-NMs, along with design strategies for their integration with hydrogels. Furthermore, we examine the detailed roles and mechanisms of EPFR-NHs in facilitating wound healing at various stages, providing direction and guiding principles for the design and clinical application of EPFR-NHs.