Electrospun polycaprolactone/gelatin submicro/nanofibrous membranes loaded with ATT/γ-Fe₂O₃ enhance vascularization and osteogenesis under a static magnetic field.

Currently, the development of multifunctional scaffolds that synergistically promote osteogenesis and angiogenesis remains a significant challenge in bone tissue engineering. It is increasingly recognized that scaffolds composed of a single material or possessing a single function are often inadequate, as they fail to mimic the complex biochemical and physical microenvironments. In this study, we successfully fabricated a submicro/nanofibrous membrane using electrospinning technology, which creates a biomimetic extracellular environment through a polycaprolactone (PCL) / gelatin (GEL) matrix. The incorporation of attapulgite (ATT) supplies essential osteogenic ions, while γ-iron oxide (γ-Fe₂O₃) facilitates mesenchymal cell differentiation and imparts magnetic responsiveness. Co-culturing the membranes with human umbilical vein endothelial cells (HUVECs) and bone marrow mesenchymal stem cells (BMSCs) revealed that the membranes possessed strong biocompatibility and promoted osteogenic differentiation and angiogenesis. Both in vivo and in vitro studies suggested the involvement of the BMP2-Smad‑RUNX‑2 signaling axis in the effects of the PG/ATT/γ‑Fe₂O₃ scaffold, which also upregulated osteogenesis‑related gene expression under a magnetic field. This work offers new insights and provides a scientific foundation for advancing the use of functionalized nanomaterials in the field of bone tissue engineering.