Strontium Substituted Hydroxyapatite Grown on Graphene Oxide nanosheets Reinforced Chitosan Scaffold to Promote Bone Regeneration
The strontium substituted hydroxyapatite (SrHA) is a commonly used material in bone regeneration for its good osteoconductive and high alkaline phosphatase (ALP) activity. However, the SrHA nanoparticles dropped scaffolds cannot properly fit the required mechanical properties. Here, we used facile hydrothermal method to synthesize graphene oxide (GO) reinforced SrHA nanoparticles. The scaffold was fabricated using freeze drying method by incorporating SrHA/GO nanoparticles into chitosan (CS) and quaternized chitosan (QCS) mixed solution. The compressive modulus of CS/QCS/SrHA/GO scaffold reached to 438.5 kPa, which was 4-fold higher than CS/QCS scaffold. Finally, the CS/QCS/SrHA/GO scaffold did not exhibit significant cytotoxicity and higher in vitro mineralization levels and ALP activity were found in it. The results of rat skull repair indicated that the CS/QCS/SrHA/GO scaffold had a significant role in promoting bone regeneration. This study provides a new strategy for modifying hydroxyapatite to satisfy the biomedical demanding of bone tissue engineering scaffolds.