Evaluation of cross-linked chitosan microparticles for bone regeneration

Abstract

The objective of this preliminary study was to evaluate the applying of chitosan (CS)-based microparticles (MPs) in bone regeneration in vivo. The CS MPs were fabricated using our scale-up method, as previously described. Mesenchymal stem cells (MSC) were harvested from the femora and tibiae of Dark Agouti (DA) rats and seeded on CS MPs. An in vitro MSCs attachment experiment was conducted by trypsinizing the cells attached to the MPs at 5, 10, 20 and 30 h. Fluorescence images of MSCs attached to the MPs were taken at 24 and 48 h, using a LIVE/DEAD cell assay. The MSC/osteoblasts (OB) seeded on MPs were then cultured in vitro using osteogenic media and implanted into partial thickness bone defects in rat femurs. There were two groups of rats, including experimental animals and controls, for the in vivo studies. The experimental group were implanted with MSC-seeded MPs and observed at 4 and 8 weeks. The control group of rats did not receive any implant material except the stainless steel plate to support the defect. Four rats per group were used for the study. The femurs were extracted at 4 and 8 weeks post-implantation and bone formation at the defect site was analysed using radiography, microcomputed tomography (µCT) and histology. Among all groups, a significant increase in bone formation was observed in the experimental group at 8 weeks implantation. The results of this study suggested that CS MPs prove to be a successful biomaterial for bone regeneration.

Exogenous mineralization of cell-seeded and unseeded collagen–chitosan hydrogels using modified culture medium

“…Direct encapsulation of cells during gel formation can be used to facilitate homogenous cell distribution in hydrogels. Numerous natural polymers including collagen [3], chitosan [21], and composite matrices [22–25] have been employed to engineer tissues and have shown promise in bone regeneration[26]. A drawback of natural hydrogel materials is that they often lack mechanical strength and represent only the protein component of the native bone tissue.…”

Injectable porous nano-hydroxyapatite/chitosan/tripolyphosphate scaffolds with improved compressive strength for bone regeneration

“…We have adopted the fabrication procedure used by our group in previous studies [6, 10, 37, 40, 41]. The objective of this study was to obtain porous spherical scaffolds using chitosan, increase the mechanical strength of the scaffolds using nHA and characterized the scaffolds for its morphological, mechanical, physiochemical, cell attachment and cell cytotoxicity properties.…”

Effects of Chitosan-Zinc Oxide Nanocomposite Conduit on Transected Sciatic Nerve: An Animal Model Study

“…On the other hand, numerous studies have reported that the mechanical and electrical properties of different polymers have improved when ZnO NPs are incorporated into the polymeric matrices [11][12][13]. Chitosan has been used for many different biomedical applications such as drug delivery and tissue engineering due to its favorable biocompatible and biodegradable properties [14,15].…”