Spiky surface topography of heterostructured nanoparticles for programmable acceleration of multistage wound healing

Wound healing is a complex and orchestrated physiological process that involves multiple stages, including hemostasis, inflammation, proliferation, and remodeling stages. Various nanomaterials have been developed to improve the wound healing; however, most of them can only promote an individual stage of this intricate process, lacking hierarchical acceleration for multiple stages. In the present study, spiky gold-palladium heterostructured nanoparticles (AuPd SHs) were designed to possess topographical architectures on the surface of nanoparticles, capable of promoting multistage wound healing in a programmable manner. First, the spiky surface topography of AuPd SHs exhibited the potent nanobridge effect for rapid wound closure, promoting the hemostasis stage. Second, the heterostructures of AuPd SHs realized visible-light-mediated hot electron excitation and electron–hole spatial separation between Au cores and Pd spikes to efficiently generate reactive oxygen species , beneficial for the inflammation stage. Third, the spiky surface topography of AuPd SHs triggered macrophage polarization from M1 to M2 phenotype, promoting the proliferation and maturation stages. Spiky AuPd SHs with simple composition and compact structures exhibit hierarchical acceleration on multiple stages of wound healing.