title: Hydroxyapatite/polyurethane scaffold incorporated with drug-loaded ethyl cellulose microspheres for bone regeneration.
abstract: The purpose of this study is to explore and develop biodegradable scaffold for bone regeneration or tissue engineering with the capacity of controlled drug delivery. Ceftazidime as a model drug was encapsulated in ethyl cellulose (EC) microspheres, which were subsequently incorporated in a hydroxyapatite/polyurethane (HA/PU) composite scaffold to generate an antibiotic drug delivery system. HA/PU scaffolds had an interconnected pore network with an average porosity of about 83%. The presence of microspheres in the composite scaffolds was confirmed by scanning electron microscopy. The drug-loaded EC microspheres were uniformly distributed in the HA/PU scaffold matrix and showed no significant effect on the pore structure of the scaffold. Incorporation of microspheres into scaffolds significantly reduced the initial burst release, and the system exhibited a sustained release of the model drug for up to 60 days. Moreover, the scaffold with drug-loaded microspheres was proved to be an effective drug delivery system with good cytocompatibility and antibacterial properties. The novel drug-loaded microsphere/scaffold composites developed in this study are promising to serve as vehicles for controlled drug delivery in bone regeneration or bone tissue engineering.
authors.affiliation: The Research Center for Nano-Biomaterials, Analytical and Testing Center, Sichuan University, Chengdu 610064, China.
authors.forename: Haohuai
authors.initials: H
authors.lastname: Liu
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Pujiang
authors.initials: P
authors.lastname: Shi
authors.forename: Qin
authors.initials: Q
authors.lastname: Zou
authors.forename: Yi
authors.initials: Y
authors.lastname: Zuo
authors.forename: Yubao
authors.initials: Y
authors.lastname: Li
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D001861:Bone Regeneration / Q000187:drug effects*; D002442:Ceftazidime / Q000008:administration & dosage; D002460:Cell Line; D002482:Cellulose / Q000031:analogs & derivatives; D016503:Drug Delivery Systems / Q000379:methods*; D017886:Durapatite / Q000627:therapeutic use*; D006801:Humans; D008863:Microspheres; D010006:Osteoblasts / Q000166:cytology; D011140:Polyurethanes / Q000627:therapeutic use*; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D011140:Polyurethanes; C013517:ethyl cellulose; D002482:Cellulose; D017886:Durapatite; D002442:Ceftazidime