Novel Blowspun Nanobioactive Glass Doped Polycaprolactone/Silk Fibroin Composite Nanofibrous Scaffold with Enhanced Osteogenic Property for Bone Tissue Engineering

摘要

Blowspinning provides an efficient and easier way of nanofibers preparation that mimics the structure of native extracellular matrix (ECM) and can be applied as scaffolds to regenerate bone tissue at the defect site. The present study reports fabrication of nanofibrous scaffold with novel polymeric combination using polycaprolactone (PCL) and silk fibroin (SF), doped with nanobioactive glass (nBS). The PCL/SF nanofibers of average diameter 570 nm were obtained by blowspinning technique, and BS nanoparticles of 80 +/- 20 nm were produced by sol-gel method followed by ball milling. On nBS doping, the resulting 3D composite matrix exhibited excellent surface property, 85-86 % porosity, 2.2 MPa mechanical strength and were effectively colonized by umbilical cord blood derived human mesenchymal stem cells (hMSCs). The nanofibrous-composite scaffolds (PCL/SF/nBS) were superior to PCL and PCL/SF scaffolds in facilitating cell attachment, metabolic activity and distribution. The PCL/SF/nBS scaffolds promoted osteogenic differentiation of hMSCs as evident by immunofluorescence of Runt-related transcription factor 2 (RUNX2) and osteoclacin (OCN) in cell ECM, and upregulation of alkaline phosphatase, RUNX2, OCN and osteopontin genes. Incorporation of nBS into the nanofibrous structure resulted in enhanced biomineralization, thereby improving osteogenic differentiation potential. Thus blowspun PCL/SF/nBS scaffolds were demonstrated to be suitable platform for bone tissue engineering applications.