Functional hydrogel wound dressings for wound healing and localized drug delivery: materials design, mechanisms, and biomedical applications

Hydrogels are increasingly explored as functional wound-dressing materials because they combine high water content, biocompatibility, structural tunability, and the ability to localize therapeutic delivery at injured tissue. As biomaterial platforms, hydrogel dressings can maintain a moist microenvironment, absorb exudate, protect the wound bed, and carry bioactive agents that modulate infection, inflammation, oxidative stress, and tissue regeneration. This review examines hydrogel wound dressings from a materials centered perspective. First, skin structure, wound-healing physiology, and major barriers to repair are outlined to define the biological requirements for effective dressings. Next, the chemical composition of natural, synthetic, and composite hydrogels, their crosslinking strategies, swelling behavior, and drug-loading and release mechanisms are discussed in relation to wound healing performance. Recent progress in infection responsive, stimuli responsive, growth factor delivering, antimicrobial peptide loaded, and self-healing hydrogel systems is then summarized. The present review highlights how composition, network architecture, and responsiveness govern biomedical function and localized drug delivery in wound care. These insights provide a materials centered framework that connects hydrogel composition, network architecture, responsiveness, and localized delivery behavior with wound healing performance, thereby supporting the rational design of next generation hydrogel biomaterials for difficult to heal wounds.