Janus Coaxially Electrospun Poly( p -dioxanone)/Polycaprolactone Core–Shell Fibrous Dura Mater Incorporating Sr/Ce-Doped Bioactive Glass for Immunomodulation and Enhanced Dural Regeneration

Repair of large dura mater defects is hindered by excessive inflammation, cerebrospinal fluid leakage, and insufficient regeneration. In this study, a Janus-bilayer artificial dura mater (SCPM) was fabricated via coaxial electrospinning, consisting of a polycaprolactone (PCL) hydrophobic layer, a PCL core, and a poly(p-dioxanone) shell incorporating 4Sr15CeBG. The exudate can undergo spontaneous ’pumping’ from the hydrophilic base layer to the hydrophobic top layer, while maintaining excellent drug delivery capability with a well-structured core–shell structure. The resulting core–shell fibrous scaffold exhibited stable mechanical performance with a tensile strength of approximately 5 MPa and controlled degradation behavior. SCPM-3 demonstrated optimal biocompatibility, with L929 and RAW264.7 cell viabilities exceeding 110% at day 3 and hemolysis rates below 5%. The scaffold significantly reduced intracellular reactive oxygen species levels, promoted macrophage polarization toward the M2 phenotype, decreased TNF-α and IL-1β secretion, and increased TGF-β and IL-10 secretion. In a rat dural defect model, SCPM-3 accelerated neodura formation, enhanced angiogenesis, reduced inflammation and adhesion, and produced continuous, well-organized collagen deposition by postoperative day 14. These results demonstrate that encapsulation of SrCeBG combined with a coaxial fibrous architecture enables safe, immunomodulatory, and effective dura mater regeneration.