From dry powder to multi-functional hydrogel: a self-healing and shape-adaptive dressing for improving diabetic wound healing

The hydrogel powder dressing is fabricated by lyophilization and mechanical ground. • The dressing shows adaptability to irregular wounds and good dimensional stability. • Dry powder-to-gel transition facilitates easy and painless dressing replacement. • The dressing enriches matrix metalloproteinase-9 and fastens diabetic wound healing. Diabetic wounds remain a major clinical challenge due to the dysregulation of inflammatory phase and impaired cellular activity. Although hydrogel sheet dressings have demonstrated a great potential, their application to irregular wounds and the ability to improve wound healing are often limited. In this study, a practical hydrogel powder dressing (O3C-H30LP) was developed from the OGCB precursor suspension which contained oxidized sodium alginate, gelatin, calcium carbonate microspheres and borax. The suspension exhibited an excellent injectability. After gelation and crosslinking, the hydrogel was freeze-dried and mechanical ground to obtain O3C-H30LP. The swelling ratio was 517.02 ± 11.02% and showed a good dimensional stability. The particle size was 109.8 ± 8.9 μm; after rehydration, they were integrated together to demonstrate a high self-healing ability. In addition to favorable biodegradability, in vitro studies showed that the sample possessed good hemocompatibility and promoted adhesion and proliferation of murine fibroblasts. Furthermore, in vivo tests based on diabetic rat model revealed that O3C-H30LP significantly accelerated wound closure during the critical stages of healing, enriched matrix metalloproteinase-9 (MMP-9), modulated the wound microenvironment, and effectively promoted tissue remodeling. This multifunctional dressing provides a simple yet efficient strategy for the management of diabetic wounds. Schematic illustration for the preparation of OGCB dry powder and its application on a diabetic wound. Download: Download high-res image (181KB) Download: Download full-size image