Studies on Hydroxyapatite/Polyurethane Scaffold Containing Drug-loaded Microspheres for Bone Tissue Engineering

To explore and develop scaffold for bone regeneration or tissue engineering with the capacity of con-trolled drug delivery,the feasibility of hydroxyapatite/polyurethane(HA/PU) scaffold containing drug-loaded mi-crospheres for controlled drug delivery system was demonstrated.Ciprofloxacin hydrochlorid as a model drug was encapsulated in ethyl cellulose(EC) microspheres,which were subsequently incorporated into HA/PU composite scaffold to generate an antibiotic drug delivery system.The results show that EC microspheres are uniformly dis-tributed in the HA/PU scaffold matrix and display no significant effect on the pore structure of the scaffold.Com-pared with incorporating ciprofloxacin hydrochlorid into scaffolds directly,embedding microspheres into scaffolds significantly reduces the initial burst drug release and extends the release time of drug delivery.In vitro drug deliv-ery tests and antibacterial activity tests prove that drug-loaded microsphere/scaffold system has good drug delivery properties and effective antibacterial properties.These results suggest that the novel drug-loaded microsphere/ scaffold composites developed in this study is a good candidate scaffold with the function of bone repair and infec-tion treatment for bone tissue engineering.