Immobilization of carboxymethyl chitosan/laponite on polycaprolactone nanofibers as osteoinductive bone scaffolds

The side effects and high cost of growth factors and drugs in bone tissue engineering have led to outstanding investigations of alternative osteoinductive supplements. Herein, the electrospun polycaprolactone (PCL) nanofibers were immobilized with carboxymethyl chitosan (CMC) and laponite nanoplatelets (LAP, 0.5-3.5 wt%) to fabricate osteoinductive scaffolds for bone tissue engineering. The Fourier-transform infrared)FTIR(and energy dispersive X-ray (EDX) spectroscopy confirmed the chemical immobilization of CMC and LAP on the surface of PCL nanofibers. Water contact angle measurements exhibited significant improvement of surface hydrophilicity for immobilized scaffolds (<10°) comparing to the virgin PCL nanofibers (125°). The immobilization of CMC and LAP enhanced the attachment, proliferation, and osteodifferentiation of the seeded human bone marrow mesenchymal stem cells (hBM-MSCs), as evidenced by increased calcium deposition, alkaline phosphatase (ALP) activity, and Osteonectin gene expression. Therefore, the fabricated scaffolds can serve as an appropriate substrate to support the proliferation and differentiation of stem cells to osteoplasts without any external osteoinductive stimulation.