Electrospun Poly(ε-Caprolactone)/Silk Fibroin Coaxial Core-Sheath Nanofibers Applied to Scaffolds and Drug Carriers

Developing biologically mimetic nanofibers (NFs) is crucial for their applications as scaffolds in tissue engineering and drug carriers. Herein, we present a strategy to facilely fabricate core-sheath NFs using coaxial electrospinning technique. Poly(ε-caprolactone) (PCL) and silk fibroin (SF) were employed as component materials to construct PCL/SF NFs with PCL cores uniformly encapsulated by SF sheaths. Scanning electron microscopy and transmission electron microscopy demonstrate a uniform core-sheath structure of the coaxial NFs. The engineered core-sheath structure confers the composite NFs with greatly improved properties including surface hydrophilicity and mechanical properties. In vitro cell culture validates that the core-sheath NFs are favorable to the cultured rat pheochromocytoma cells (PC 12) attachment. To further demonstrate the advantage of the coupled structural integrity, the PCL/SF core-sheath NFs were compared with the NFs produced from PCL and SF blend. Results showed that the PCL/SF NFs possessed a tensile strength of ~6.93 ± 0.52 MPa and an elongation at break of ~294.31 ± 24.17%, whereas the blend NFs possessed ~5.55 ± 0.50 MPa and ~88.05 ± 13.98%, respectively. Dexamethasone-phosphate sodium (DEX) was employed as a model drug, whereby the in vitro release study indicates that the NFs exhibit an ideal releasing profile, capable of releasing DEX continuously over a period of 450 h. The constructed PCL/SF core-sheath NFs are promising candidates for biomedical applications. POLYM. ENG. SCI., 60:802–809, 2020. © 2020 Society of Plastics Engineers