Wet chemical process to enhance osteoconductivity of electrospun chitosan nanofibers

Abstract

In this study, chitosan/hydroxyapatite (CS/HA) nanofibers were prepared using a wet chemical method. First, CS nanofibers with uniform diameters were fabricated using electrospinning. Then, a wet chemical process was used to mineralize nanofiber surfaces to form a homogeneous HA deposit. Reactions with three cycles were found to optimize biomimetic properties of the HA. The mineralization process required only approximately 3 h, which corresponded to a saving of 98% in preparation time compared with that needed by the process using a simulated body fluid (SBF). According to the attachment and spreading of UMR (rat osteosarcoma) cells on the CS/HA composite fibers, the deposited mineralization layer significantly enhanced cell affinity of the CS nanofibers and the HA created by the wet chemical method was as effective as that created by the SBF. The composite nanofibrous scaffolds produced by the wet chemical process also promoted osteogenic differentiation by inducing ossification. Thus, expressions of collagen type I, alkaline phosphatase, osteocalcin, bone sialoprotein, and osterix were all enhanced. These results demonstrated that composite electrospun fibers can be efficiently prepared using wet chemical method and the resulting nanofibrous scaffolds have considerable potential in future bone tissue engineering applications.