Carboxymethyl chitosan/sodium alginate-based micron-fibers fabricated by emulsion electrospinning for periosteal tissue engineering

Periosteum provides nourishment to bones and facilitates osteogenesis. The structural and functional impairment of periosteum can cause bone regeneration difficulties. Artificial periosteum with suitable mechanical properties and chemical composition can effectively guide bone tissue regeneration. In this study, a polycaprolactone (PCL)/carboxymethyl chitosan (CMCS)/sodium alginate (SA) micron-fibrous bionic periosteum was prepared. The water-in-oil PCL-CMCS/SA emulsion was prepared by using Span 80 as the emulsifier, and the PCL/CMCS/SA composite micron-fibers were fabricated by emulsion electrospinning. The physicochemical properties of the PCL/CMCS/SA micron-fibers were investigated via SEM, FTIR and tensile test analyses. CCK8 assay, live/dead assay, cell adhesion, and qPCR tests were carried out to evaluate the osteoinductive capacity of the micron-fibers and their biocompatibility to MC3T3-E1 osteoblasts. The results showed that CMCS and SA were successfully immobilized in the micron-fibers. The PCL/CMCS/SA micron-fibers showed an average diameter of 2.381 ± 1.068 μm with excellent tensile strength. The PCL/CMCS/SA composite scaffold demonstrated no significant cytotoxicity and could facilitate osteoblast adhesion. In addition, it could upregulate the early expression of osteogenic genes ALP and Runx2. The PCL/CMCS/SA micron-fibers prepared by emulsion electrospinning showed good mechanical properties, excellent biocompatibility and osteoinductive capacity to osteoblasts, and could be used as potential transplantable scaffolds for repairing large-segment bone defects.