Calcium phosphate bioceramics with polyvinyl alcohol hydrogels for biomedical applications

Abstract

Polyvinyl alcohol (PVA) hydrogels show desirable characteristics to use as a biomaterial especially for soft tissue replacement. However, their bio inertness restricts their application in vivo. In this study, polyvinyl alcohol was blended with bi-phasic calcium phosphate and to develop a composite hydrogel by a physical freeze-thawing method, followed by annealing treatment. The synthesized bi-phasic calcium phosphate (BCP) and composite hydrogels were characterized by SEM, XRD and FTIR. The concentration of BCP was optimized and it was found that BCP modifies the hydrogel network by developing the secondary electrostatic bonding between matrix and reinforcement. The highest tensile and compressive strength could reach 5.2 ± 0.6 MPa and 14.9 ± 0.3 MPa respectively for PVA/2.5BCP and they exhibit time-dependent, rapid self-recoverable and fatigue resistant behavior based on the cyclic loading-unloading compression test. Similar observations were found for viscoelastic properties which are relevant for the tissue engineering application. Friction study showed the composite hydrogel had a cartilage-like frictional response, dominated by the interstitial fluid support. Besides composite hydrogel showed excellent antimicrobial activity against bacterial species, Escherichia coli, Staphylococcus aureus and Candida albicans fungi, and the cytocompatibility towards L929 fibroblast cells provides a potential pathway to develop a hydrogel as a promising substitute for tissue engineering scaffold material. © 2019 IOP Publishing Ltd.