Organic–Inorganic Dual‐Nanofiber Interpenetrating Network Scaffolds for Complementary Enhancement of Mechanical Stability and Osteogenic Bioactivity

ABSTRACT Incorporating nanofibers into 3D‐printed scaffolds is an effective strategy to enhance the physicochemical properties and osteogenic bioactivity of bone tissue engineering constructs. In this study, we developed a composite scaffold featuring a dual‐nanofiber interpenetrating network composed of silica (SiO 2 ) and poly(L‐lactic acid)/gelatin (PLLA/GEL) nanofibers. SiO 2 nanofibers were employed to reinforce mechanical properties and release bioactive Si elements, establishing a favorable osteogenic microenvironment. Concurrently, PLLA/GEL nanofibers were chemically crosslinked with the sodium alginate (SA) matrix to stabilize the scaffold structure. This design effectively addresses the structural instability often observed in single‐component inorganic fiber systems. Notably, systematic comparative experiments clarified the distinct contributions of each component. Results indicated that PLLA/GEL nanofibers primarily contributed to mechanical stability; however, their osteogenic contribution was not significantly superior to PLLA particles. In contrast, SiO 2 nanofibers exhibited superior bioactivity compared to nanoparticles in inducing osteogenic differentiation and promoting pro‐reparative macrophage polarization, leading to enhanced in vivo bone repair. This dual‐nanofiber network complementarily improves mechanical stability, modulates inflammation, and promotes osteogenic efficacy, offering a novel strategy for designing high‐performance functional bone tissue engineering scaffolds.