A One-Step, Cell-Ready Collagen Bioink Enabling DLP Bioprinting and Enhanced Healing of Diabetic Wounds

Collagen-based bioinks are highly desirable for regenerative biofabrication owing to their intrinsic bioactivity and native triple-helical structure; however, their application in light-based bioprinting is severely constrained by poor solubility, limited photocurability, and incompatibility with direct cell delivery under physiological conditions. Here, we report a one-step, cell-ready itaconylated collagen (CIA) bioink that enables visible-light digital light processing (DLP) bioprinting at neutral pH. CIA dissolves readily in aqueous media to form transparent precursor solutions suitable for rapid photo-crosslinking and high-fidelity fabrication. Compared with collagen methacrylate (CMA), CIA exhibits superior solubility, printability, and cytocompatibility while preserving collagen biofunctionality. CIA supports direct encapsulation of multiple cell types with high viability and enables fabrication of well-defined porous constructs. In a diabetic wound model, CIA hydrogels accelerated wound closure, reduced inflammation, enhanced angiogenesis, and promoted tissue remodeling. These findings establish CIA as a practical collagen bioink for cell-enabled DLP bioprinting and regenerative wound repair.