Polycatechin nanoparticle-enhanced hydrogel as a multifunctional platform for targeted diabetic oral ulcer repair

Injectable HGL2 hydrogel forms in situ for infected diabetic oral ulcers. • Polycatechin nanoparticles provide broad ROS scavenging to relieve oxidative stress. • Quaternized chitosan confers rapid antibacterial action against oral pathogens. • HGL2 accelerates angiogenesis and mucosal regeneration, achieving near closure. Diabetes-associated oral ulcers represent a difficult-to-treat mucosal wound type characterized by persistent inflammation and delayed tissue regeneration. In such lesions, excessive oxidative stress, bacterial colonization, and insufficient angiogenesis synergistically compromise healing outcomes and limit the effectiveness of conventional topical therapies. However, a single therapeutic platform that can concurrently mitigate infection and redox imbalance while providing structural support for mucosal remodeling remains largely unavailable. Here, we show an injectable and in situ forming polysaccharide hydrogel patch (HGL2) composed of polycatechin nanoparticles, oxidized β-glucan, and quaternized chitosan for targeted ulcer care. Our results demonstrate that this system exhibits potent antimicrobial efficacy against Staphylococcus aureus and Escherichia coli alongside superior radical scavenging capabilities to reshape the hostile wound microenvironment. Furthermore, the multifunctional network enhances cellular survival under oxidative stress and promotes robust angiogenesis to achieve rapid lesion closure in diabetic rodent models. Collectively, our hydrogel provides a clinically deployable strategy for synchronizing antimicrobial action and tissue reconstruction in the management of complex diabetic mucosal wounds. Download: Download high-res image (236KB) Download: Download full-size image