Mimicked hybrid hydrogel based on gelatin/PVA for tissue engineering in subchondral bone interface for osteoarthritis surgery

Osteoarthritis (OA) is a degenerative joint disease of the articular cartilage and extends to the subchondral bone. The interface between these soft and hard tissues has a significant role in OA. In this work, gelatin/PVA hydrogels in different ratios of 100:0, 70:30, 50:50, 30:70, and 0:100 were prepared by chemical and freeze-thaw physical crosslinking. The molecular organization and morphology were characterized and observed by FTIR and SEM, respectively. The physical properties of swelling ratio, degradation rate, and compressive strength were evaluated. The hydrogels were cultured with osteoblasts before evaluation of cell adhesion and proliferation, ALP activity, calcium deposition, and calcium content. The gelatin/PVA formed hydrogels via crosslinking of chemical bonding and molecular interaction. The morphology demonstrated that the pore sizes decreased as the proportion of PVA increased and the swelling ratio and degradation rate increased as the proportion of gelatin increased. The compressive strength increased as the proportion of PVA increased. The biological function tests showed that gelatin/PVA supported cell adhesion and proliferation, ALP activity, calcium deposition, and calcium content. Finally, the gelatin/PVA ratio of 30:70 demonstrated suitable structural formation, physical properties, and biological functions to induce tissue formation at the subchondral bone interface for OA surgery.