Surface Modification Of PHBV Fibrous Scaffold For Enhancing Their Biocompatible

The expansion in vitro of chondrocyte and BMSCs has limited the development of cartilage tissue engineering. It is an effective strategy to enhance proliferation of seeding cells by bioactive scaffolds, which can provide three-dimension environment for cell living by simulating the structure of extracellular matrix. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a nature occurring aliphatic polyesters synthesized by bacteria under an unbalance condition. It possesses many excellent properties such as renewability, biocompatibility, non-toxicity and biodegradability which make it can be widely used in biomedical field, such as surgical suture, wound dressings, vascular graft, scaffolds in tissue engineering and drug carriers. However, the poor bioactivity and hydrophobicity of PHBV have seriously affected cell attachment and restricted its further application in tissue engineering. Therefore, in order to enhance the efficacy of PHBV in tissue engineering application, surface modification is required to improve its hydrophilcity and bioactivity.In this study, PHBV fibrous scaffolds have been fabricated via electrospinning method. In order to improve their hydrophilicity and bioactivity, dextran, glucosamine or gelatin has been grafted onto the surface of PHBV fibrous scaffold by chemical modification, respectively. During surface modification process, we have explored the influence of modification parameters on the grafted rate by staining method. The Fourier transform infrared spectroscopy and water contact angle measurement were carried out to characterize the pure and modified PHBV scaffold. Experience results showed that the dextran, glucosamine and gelatin had been successfully grafted onto the surface of PHBV and significantly improved the hydrophilicity of PHBV fibrous scaffold. The results of degradation experiment showed that chemical modification has improved the degradation rate of PHBV. In order to investigate the influence on cytocompatibility of modified PHBV scaffold, the proliferation of chondrocyte and bone marrow-derived mesenchymal stem cells (BMSCs) incubated on different scaffold were tested by the Alamar Blue assay. The result showed that all modified PHBV fibrous scaffolds could improve the proliferation of chondrocyte, however only the dextran modified PHBV scaffold could enhance the proliferation of BMSCs. All the experiment results showed these three different modified PHBV fibrous scaffolds could be a potential scaffolds applied in cartilage tissue engineering.