Innovative advances and future perspectives in injectable hydrogels for wound healing: a comprehensive review

Injectable hydrogels constitute a highly versatile and promising class of biomaterials for therapeutic use in both acute and chronic wounds. Engineered to mimic the structural and functional attributes of the native extracellular matrix (ECM), these hydrogels form a biomimetic, hydrated three-dimensional network that facilitates critical wound healing processes, such as cellular infiltration, angiogenesis, and extracellular matrix remodeling. Composed of a broad spectrum of biocompatible polymers, including naturally derived polysaccharides, such as alginate, hyaluronic acid, and chitosan, along with various synthetic polymers such as polyethylene glycol and polyvinyl alcohol injectable hydrogels can be precisely tailored in terms of viscoelastic properties, degradation kinetics, and bio-functionalization to meet specific clinical requirements. Their minimally invasive administration through a syringe or catheter, combined with in situ gelation triggered by physiological stimuli, such as pH, temperature, or ionic strength, allows conformal adaptation to complex wound geometries while minimizing surgical trauma. Furthermore, these hydrogels serve as adaptable scaffolds for the spatial and temporal controlled delivery of therapeutic agents, including growth factors, antimicrobial compounds, stem cells, and extracellular vesicles, enabling dynamic modulation of the wound microenvironment. Such functionalities facilitate regulated inflammation, oxidative stress mitigation, and tissue regeneration. Despite their substantial potential, challenges persist regarding mechanical stability under physiological load, immunomodulatory capacity, and regulatory pathways for clinical translation. Recent advancements-such as the integration of nanostructured components, stimuli-responsive crosslinking mechanisms, and bio-orthogonal chemistries-have expanded the functional capabilities of injectable hydrogels and improved their therapeutic efficacy. This review offers a comprehensive analysis of the present status and future directions of injectable hydrogel systems for wound healing, emphasizing innovative material strategies, delivery mechanisms, and translational hurdles. These insights highlight the critical role of injectable hydrogels in advancing the development of next-generation, precision-guided wound management technologies.