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[Display omitted] • A H 2 -realeasing MN patch realeases hydrogen at the deep site of diabetic wound continually. • Self-responsive H 2 -releasing microneedle patch accelerates diabetic wound healing by sequential action of H 2 and Co2+. • Sequential release of H 2 and Co2+ is achieved through the interaction of the microneedle and the backing. • An MN patch achieving integration and spatiotemporal control of antibacterial, ROS regulation, and proangiogenic functions. Oxidative stress regulation and synchronized promotion of angiogenesis are critical factors in the healing process of diabetic wounds. However, existing research often fails to fully consider the dynamic interplay between these two biological processes and their time-dependent roles in diabetic wound healing. This study innovatively introduces a novel hydrogen (H 2)-releasing microneedle patch capable of precisely controlling the regulation of oxidative stress and the promotion of angiogenesis through a bidirectional responsive mechanism of microneedles and backing layers. Specifically, we employ ammonia borane (AB)-loaded mesoporous silica nanoparticles (MSN) as a source of H 2 , combined with polyvinyl pyrrolidone (PVP) to fabricate microneedles. This design effectively clears excessive reactive oxygen species (ROS) in deep tissues and promotes the M2 polarization of macrophages. Concurrently, we utilize cobalt-adsorbed graphene oxide (GO/Co2+) mixed with polyvinyl alcohol (PVA) to prepare backing layers, which not only release Co2+ upon the reduction of oxygen-containing functional groups in GO by H 2 diffused from deep tissues to synergize with H 2 for enhanced vascularization, but also endow the microneedle patch with near-infrared (NIR) light-responsive antimicrobial properties, crucial for managing diabetic infected wounds. Through this innovative dual-action mechanism, our research significantly accelerates the healing process of infected wounds in a diabetic mouse model. Moreover, single-cell sequencing results further confirm the pivotal role of H 2 in regulating oxidative stress, promoting macrophage M2 polarization, and stimulating angiogenesis. These results not only showcase the unique features of our microneedle patch but also offer new perspectives and therapeutic strategies for the treatment of diabetic wounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Aerogel phase in HAB-gel endows it with self-negative-pressure exudate absorption. • Hydrogel phase in HAB-gel shows excellent natures in liquid absorption and retention. • The LPU with end-capping l -cys possesses significant M2-macrophage polarization. • After β-CD loaded with PHMB, the HAB-gel shows excellent antibacterial properties. Chronic wound healing is a major and unmet challenge, due to contamination of exudate, bacterial infection and non-healing symptoms, having become urgent an problem to be solved. Developing multifunctional dressings capable of efficiently absorbing exudate by forming self-micro-negative pressure, effectively antibacterial and inducing immune regulation, would be a promising strategy for wound healing. Herein, the hydrogel-aerogel biphase gel (HAB-gel) dressing consisted of PVA grafted with PAM and bio-based polyurethane was prepared to generate synergistic therapeutic effects through removing exudates, antibacterial properties and immune regulation. The PVA grafted with PAMs features generating self-negative pressure to absorb deep exudate by aerogel phase, providing a comfortable microenvironment for wound healing, moreover, the capacities of liquid absorption and retention are enhanced by hydrogel phase, preventing wounds from exudate contamination. The incorporation of β-cyclodextrin (β-CD) in the constructed polyurethane (LPU) endows the HAB-gel materials with excellent antibacterial properties after being loaded with polyhexamethylene biguanidine (PHMB). Furthermore, the HAB-gel dressing can accelerate the macrophage polarization into anti-inflammatory M2 via the hydrogen sulfide (H 2 S) generation, angiogenesis promotion and collagen deposition in periwound tissue. Overall, this novel strategy for synergistic treatment of chronic wounds, provides a promising method for the management of tissue regeneration disorders. [ABSTRACT FROM AUTHOR]

• We explore a self-assembled hydrogel composed of cinnamaldehyde and folic acid. • The gel integrates easy absorption, satisfied injectability, self-healing property. • The gel promotes wound healing via multifunctional effects. • The gel induces anti-inflammatory macrophages from pro-inflammatory macrophages. Wound healing is one of the major challenges in biomedicine owing to the absence of ideal wound dressings which can integrate easy absorption, satisfied injectability, rapid self-healing property, and multiple therapeutic effects into one system. Here, we explore a self-assembled supramolecular hydrogel composed of herbal cinnamaldehyde (CA) and folic acid (FA). This enables the Schiff base and the Ionic crosslinking as a dynamic double cross-linked network. This nano-scale hydrogel (C-FA-gel) maintains good adhesion and is apt to get peeled off from tissues without any residuals. Further experiments show a percutaneous absorption within 12 h after the hydrogel dressing perfectly fills the irregular wound by injection on pig skin. For muti-target therapeutics, the drug sustained-release of C-FA-gel exhibits broad-spectrum antibacterial activities without evident cytotoxicity. Besides, the topical dressing on rat skin promotes wound healing via multifunctional effects including inflammatory reduction, facilitation of the angiogenesis improvement, and regeneration promotion of skin appendages. Moreover, the C-FA-gel induces anti-inflammatory macrophages from pro-inflammatory macrophages. Therefore, we successfully present a self-assembled hydrogel using the 'one system' strategy. This study offers a green and efficient design for the potential to be applied to complicated wound treatment. [ABSTRACT FROM AUTHOR]