A Janus nano-bioactive glass-loaded PPDO/PCL bilayer electrospun fibrous membrane with directional fluid transport and regenerative functions for cranial periosteum repair

Cranial periosteum defects are frequently accompanied by cerebrospinal fluid (CSF) leakage and insufficient regenerative capacity, posing significant clinical challenges. In this study, a Janus nano-bioactive glass (nBG)-loaded PPDO/PCL bilayer electrospun fibrous membrane was designed to simultaneously achieve directional fluid transport and osteogenic regeneration. The asymmetric hydrophilic/hydrophobic architecture enabled unidirectional liquid management, with the hydrophobic layer exhibiting a water contact angle of 145° and the hydrophilic layer showing rapid wetting within 0.8 s. The membrane demonstrated suitable mechanical flexibility, with a tensile strength of 3–4 MPa, meeting periosteal repair requirements. In vitro assays revealed excellent cytocompatibility, with cell viability exceeding 100% over 5 days. Notably, the PPDO/BG-PCL group promoted cell proliferation above 110% on days 3 and 5 and showed negligible hemolysis. nBG enhanced osteogenic differentiation, as evidenced by increased ALP activity at 7 and 14 days and dense calcium nodule formation at 28 days. Moreover, apatite-like hydroxyapatite uniformly covered the fiber surface after 28 days of mineralization. Collectively, this Janus PPDO/BG-PCL membrane integrates effective CSF leakage prevention with sustained bioactive stimulation, representing a promising scaffold for cranial periosteum repair.