Advanced hydrogels for diabetic wound healing: From functionalized design, controlled preparation to application performance evaluation

Diabetic wounds present significant challenges in healing due to their complex pathological microenvironment, characterized by persistent inflammation, impaired angiogenesis, oxidative stress, and heightened susceptibility to infection. Hydrogel dressings, with their biomimetic three-dimensional structures, tunable physicochemical properties, and multifunctional integration capabilities, emerge as an ideal choice for managing diabetic wounds. This review systematically elucidates the pathological characteristics and healing mechanisms associated with diabetic wounds, analyzes modification strategies for both natural and synthetic polymeric materials, and evaluates their respective advantages and limitations in promoting wound healing. It highlights design innovations in smart hydrogels, focusing on structural adaptability (self-healing, injectability), interfacial properties (moisture adhesion and on-demand removal), and microenvironment responsiveness (pH, enzymes, glucose, reactive oxygen species, etc.). Furthermore, it delves into the mechanisms and efficacy of antimicrobial, antioxidant/anti-inflammatory, pro-angiogenic, and multifunctional synergistic hydrogels. A multidimensional efficacy evaluation system encompassing wound closure rates, epithelial regeneration, angiogenesis, and infection control is established, alongside biosafety assessment standards based on cytotoxicity, hemocompatibility, and animal testing. Finally, future directions are outlined, including the development of smart integrated hydrogels, clinical translation strategies, and in-depth studies of underlying mechanisms, providing theoretical foundations and technical support for the advancement and clinical application of functional hydrogel dressings.