3D printable hydrogel inks with metal-organic frameworks for sustained small drug delivery in wound healing.

Wound healing is a complex and dynamic biological process, and impaired healing can lead to prolonged recovery and increased healthcare costs. Recent advancements in wound healing therapeutics include hydrogel-based biomaterials, nanocarrier-mediated drug delivery systems, and tissue-engineered scaffolds that aim to modulate the wound microenvironment and accelerate tissue regeneration. However, wound healing remains a clinical challenge, particularly when sustained delivery of therapeutic agents and conformal wound coverage are required. Herein, we develop a multifunctional hydrogel system composed of hyaluronic acid modified with methacrylate and a zirconium-based metal-organic framework (MOF), enabling enhanced structural control and drug retention. The resulting hydrogel exhibits tunable photo-crosslinking kinetics, allowing precise gelation behavior and extrusion-based 3D printing without the need for a support bath. Moreover, the integration of hydrophobic and rigid MOF particles significantly suppresses water uptake, imparting anti-swelling properties that facilitate the sustained release of hydrophobic drugs such as quercetin. When applied to a wound healing model, the proposed platform promotes fibroblast migration and tissue regeneration over an extended period, highlighting the therapeutic potential of controlled drug release. Thus, this hydrogel offers a structurally robust, printable, and drug-releasing biomaterial platform for next-generation wound dressings.