A Novel Chitosan-Modified PLA Doped n-HA Bone Scaffold

Based on the principles of bionics, the hydrophilicity, bacteriostasis, and alkalinity of chitosan (CS) have been utilized to enhance the hydrophilic and antibacterial properties of a polylactic acid (PLA) bone scaffold. They also neutralize the acidity generated by its degradation. The incorporation of nano-hydroxyapatite (n-HA) effectively improves the osteogenic properties of PLA. The PLA-CS graft was first synthesized by grafting CS onto PLA using ferulic acid (FA), resulting in a CS-modified, PLA-doped n-HA (PLA-CS/n-HA) bone scaffold. The prepared PLA-CS/n-HA bone scaffold facilitated the formation of new bone and tissue attachment. More importantly, the acidity from PLA degradation in the PLA-CS/n-HA scaffold was alleviated to a certain extent. Its hydrophilicity and compressive strength were enhanced compared to the PLA bone scaffold, and its antibacterial activity was stronger against Staphylococcus aureus than against Escherichia coli. After a 12 h co-culture with the PLA-CS/n-HA bone scaffold, the relative adhesion rate of MC3T3-E1 cells was 118.95%. After 14 days of inducing MC3T3-E1 cells on the PLA-CS/n-HA bone scaffold, the MC3T3-E1 cells exhibited preliminary differentiation and alkaline phosphatase activity reached 1.23. The PLA-CS/n-HA bone scaffold received a cytotoxicity grade of class 0, indicating no cytotoxicity.