Hydrogel Encapsulating Wormwood Essential Oil with Broad-spectrum Antibacterial and Immunomodulatory Properties for Infected Diabetic Wound Healing.

The integration of hydrogels with bio-friendly functional components through simple and efficient strategies to construct wound dressings with broad-spectrum antibacterial and immunomodulatory properties to promote the healing of infected diabetic wounds is highly desirable but remains a major challenge. Here, wormwood essential oil (WEO) is effectively encapsulated in the hydrogel via an O/W-Pickering emulsion during the polymerization of methacrylic anhydride gelatin (GelMA), acrylamide (AM), and acrylic acid N-hydroxysuccinimide ester (AAc-NHS) to form a multifunctional hydrogel dressing (HD-WEO). Compared with conventional emulsions, Pickering emulsions not only improve the encapsulation stability of the WEO, but also enhance the tensile and swelling properties of hydrogel. The synergistic interaction of WEO's diverse bioactive components provides a broad-spectrum antibacterial activity against S. aureus, E. coli, and MRSA. In addition, the HD-WEO can induce the polarization of macrophages from M1 to M2 phenotype. With these advantages, the broad-spectrum antibacterial and immunomodulatory HD-WEO effectively promotes the collagen deposition and neovascularization, thereby accelerating the healing of MRSA-infected diabetic wounds.