Pollen Integrated Hydrogel Patches With Hierarchical Structures and Spatio-Temporal Actives Release for Wound Healing.

Hydrogel patches have been serving as powerful tools for wound healing. Scientific attention in this field is focused on imparting the patches with novel structures, functions, and actives for promoting wound healing. In this paper, we have developed an innovative hydrogel patch with hierarchical structure and spatiotemporal actives release for efficient wound healing. This hydrogel patch was achieved by integrating asiatic acid (AA)-loaded pollens with chlorogenic acid (CA)-containing gelatin methacryloyl (GelMA) hydrogel. The high specific surface area and nanoporous structure of the pollens-integrated GelMA promote efficient loading and release of CA and AA, respectively. In wound treatment, the outer layer of GelMA first releases CA to fight infection. With the gradual degradation of GelMA, the pollens are exposed to the wounds and released AA, intensifying anti-inflammatory effects and promoting wound healing. These features indicate that this pollen-integrated hydrogel patch significantly accelerates the wound healing process in a spatiotemporal responsive manner, demonstrating great potential for clinical applications.