The design of polycaprolactone-polyurethane/chitosan composite for bone tissue engineering

In this work, polycaprolactone-based polyurethane urea (PCLUU)/chitosan (CS) composites were fabricated and studied in terms of growth, adhesion, and differentiation of human bone marrow mesenchymal stem cells (hBMSCs) to osteoblasts. The prepared scaffolds were characterized using FT-IR, SEM, H-1 NMR, XRD, compression test, water contact angle test, TGA, and in vitro degradation assays. The enhancement of compressive strength (15.82 MPa) and thermal stability occurred due to the stronger interactions between the polymer chains of PCLUU and the CS molecules. The SEM micrographs indicated homogenous and dense morphologies for the prepared scaffold. The in vitro cytocompatibility tests confirmed the non-toxic and biocompatible nature of the prepared scaffolds. The composites promoted the formation of calcium levels and the alkaline phosphatase activity of hBMSCs. The RT-PCR analysis revealed the upregulation of Runt-related transcription factor 2 (Runx2) and osteocalcin (OCN) genes in the hBMSCs cultured on the prepared scaffold in both the growth and osteogenic medium. Alizarin red staining indicated the enhancement of extracellular calcium deposition of the hBMSCs cultured on the fabricated scaffold. Collectively, the prepared scaffold indicated extraordinary properties as a beneficial implantable scaffold in bone tissue engineering and regeneration.