Spatiotemporal self-reinforcing hydrogel spray with antibacterial and anti-inflammatory properties for accelerated diabetic wound healing.

Sprayable hydrogels present an effective strategy for treating diabetic wounds, offering ease of application and good conformity to irregularly shaped wound sites. Nonetheless, their practical use remains significantly restricted by insufficient mechanical robustness and limited multifunctionality. Therefore, developing an approach to design sprayable hydrogel that simultaneously enhances mechanical strength, broadens functional capabilities, and ensures optimal wound adaptability is critically needed. In this work, an innovative approach integrating spatiotemporal self-strengthening and sprayability is proposed for the development of hydrogel-based wound dressings. This functionality is achieved through the synergy of rapid amidation and a gradual ring-opening reaction, equipping the hydrogels with both good wound adaptability and superior mechanical stability. The incorporation of polydopamine nanoparticles (PDA NPs) enables the creation of multifunctional therapeutic hydrogels specifically designed for chronic diabetic wound treatment. The hydrogel can be effortlessly sprayed onto wounds, progressively enhance their mechanical properties, and exhibit a combination of potent antibacterial activity, efficient reactive oxygen species (ROS) scavenging, strong bioadhesion, and outstanding biocompatibility, ultimately accelerating the diabetic wound healing process. We believe that sprayable hydrogels with these advanced properties will provide valuable insights into hydrogel-based wound dressings and expand the biomedical applications of bioinspired hydrogels. STATEMENT OF SIGNIFICANCE: Sprayable hydrogels present an effective strategy for treating diabetic wounds, offering ease of application and good conformity to irregularly shaped wound sites. Nonetheless, their practical use remains significantly restricted by insufficient mechanical robustness and limited multifunctionality. Herein, an approach integrating spatiotemporal self-strengthening and sprayability is proposed for the development of hydrogel-based wound dressings. Furthermore, we have developed sprayable hydrogel dressings with spatiotemporal self-strengthening, antibacterial and anti-inflammatory properties, consisting of double-network hydrogel and polydopamine nanoparticles (PDA NPs) as a multitargeted therapeutic system for chronic diabetic wound healing. We believe that this sprayable hydrogels will provide valuable insights into hydrogel-based wound dressings and expand the biomedical applications.