Development of a Dual-Cross-Linked Collagen-Based Bioink for High-Resolution 3D Bioprinting and Antiaging

The advancement of personalized antiaging therapies demands the convergence of biomaterial innovation and precision fabrication technologies. Here, we present the development of a dual-cross-linked collagen-based bioink, integrating methacrylated collagen (CMA) and 1,4-butanediol diglycidyl ether (BDDE), tailored for DLP-based bioprinting. BDDE functions as a chemical cross-linker by forming stable ether bonds with hydroxyl groups on the collagen backbone, thereby reinforcing the structural integrity of the matrix. Subsequent photo-cross-linking of CMA generates an interpenetrating network that imparts superior enhancements to mechanical resilience, proteolytic endurance, and structural robustness. Bioink supports high-resolution cell-laden printing and enables the fabrication of geometrically complex, high-fidelity constructs. Moreover, the incorporation of bioactive retinol (VA) allows for the fabrication of functionalized hydrogel facial patches with targeted antiaging activity. <i>In vivo</i> studies were performed employing a D-galactose-induced aging model demonstrated significant improvements in dermal density, transepidermal water loss (TEWL), and antioxidant capacity. The CMA/BDDE bioink thus offers a versatile, clinically relevant platform for next-generation regenerative esthetics and personalized dermatological interventions.