| Objective:Etimicin(ETM)-loaded porous nano-hydroxyapatite(n-HA)/Chitosan(CS) cross-linking composite scaffolds were prepared by the ionic gelation method and a subsequent physical mixing and freeze-drying process, whose In vitro properties were tested.Methods:The influences of the n-HA content of the scaffolds on their porous structures and mechanical properties were investigated through scanning electron microscopy(SEM) and mechanical test. The porosity of the scaffolds was tested by a liquid displacement method. Entrapment Efficiency(EE) of the composite scaffolds was determined by measuring nonentrapped ETM in the supernatant. Meanwhile, in vitro drug-release performance of scaffolds was evaluated by incubation in simulated body fluid.Results:the composite scaffolds were characterized by a highly porous structure and the irregular pore size. In addition, little of n-HA were scattered in the scaffold and more were aggregated to form micro-particles, the porus structure has been distructed by n-HA particles. The porosity of the n-HA/CS(1:2w/w) scaffolds shown was80.1± 8.6%. Entrapment and Loading Efficiencies of the ETM-loaded n-HA/CS(1:2w/w) scaffolds tested were25.5%and12.5%. Compressive stress of the n-HA/CS(1:2w/w) scaffolds was significantly higher compared with n-HA/CS(1:1w/w) scaffolds(P<0.05). The amount of ETM released from n-HA/CS(1:2w/w) scaffolds was up to42±5.1%after12h and60.3±4.2%after1day, named as rapid release period followed by a continuous slow release period. The release lasted for more than one week.Conclusion:although its mechanical performance is not ideal, but with Further improvement of technology process, the ETM-loaded porous n-HA/CS scaffolds still could be a promising biomaterial for bone tissue engineering to treat osteomyelitis or bone defect accompanied by bacterial contamination. |
