Polydopamine immobilized icariin on 3D printed porous polylact-glycolic acid/calcium sulfate scaffold to improve osteogenesis.

Bone defects resulting from fractures, bone tumor resections, and non-unions are common clinical challenges. 3D-printed bone scaffolds offer enhanced customization and adaptability. however, their existing limitations in biological activity need to be addressed. In this study, we developed a novel composite scaffold (PLGA/CaSO4/PDA/ICA) for bone defect repair by incorporating polydopamine (PDA) and icariin (ICA) into a PLGA/CaSO4 matrix. We utilized Fused Deposition Modeling (FDM) technology to fabricate PLGA/CaSO scaffolds and employed polydopamine (PDA) for the effective loading of ICA. Characterization tests revealed that the PLGA/CaSO/PDA/ICA scaffolds exhibited excellent hydrophilicity and mechanical properties. In vitro experiments showed that the PLGA/CaSO/PDA/ICA scaffolds significantly promoted cell proliferation, migration, and osteogenic differentiation while enhancing the expression of osteogenesis-related genes. Additionally, in vivo experiments revealed accelerated bone regeneration in the PLGA/CaSO4/PDA/ICA group, displaying higher bone volume fraction (BV/TV), denser trabeculae, and deeper scaffold integration at 8 weeks. Overall, These findings highlight the synergistic role of PDA-mediated surface modification and ICA-driven osteoinduction, positioning the PLGA/CaSO4/PDA/ICA scaffold as a promising candidate for bone tissue engineering applications.