Tannic acid-mediated hydrogel crosslinking boosts diabetic wound healing via antibacterial and pro-angiogenesis

Chronic diabetic wounds represent a significant clinical challenge due to persistent bacterial infections and impaired angiogenesis. To address these issues, we developed a multifunctional hydrogel (HA-BSP-TA) by integrating Bletilla striata polysaccharide (BSP) with hyaluronic acid (HA) and post-processing it with tannic acid (TA) to confer antibacterial and pro-angiogenic properties. The HA-BSP-TA hydrogel exhibited a porous microstructure, favorable swelling capacity, robust mechanical properties, controlled degradability, and sustained TA release. In vitro experiments demonstrated its biocompatibility, antioxidant activity, effective antibacterial effects against Escherichia coli and Staphylococcus aureus, and potential pro-angiogenic capability. In vivo studies using a diabetic rat model further revealed that HA-BSP-TA significantly reduced inflammatory cell infiltration, enhanced collagen deposition, and promoted vascularization, thereby accelerating wound healing. In conclusion, this study proposes a promising therapeutic strategy for diabetic skin defects through synergistic antibacterial, antioxidant and pro-angiogenic mechanisms.