title: Fabrication and in vitro characterization of bioactive glass composite scaffolds for bone regeneration.
abstract: Here we fabricate and characterize bioactive composite scaffolds for bone tissue engineering applications. 45S5 Bioglass® (45S5) or strontium-substituted bioactive glass (SrBG) were incorporated into polycaprolactone (PCL) and fabricated into 3D bioactive composite scaffolds utilizing additive manufacturing technology. We show that composite scaffolds (PCL/45S5 and PCL/SrBG) can be reproducibly manufactured with a scaffold morphology highly resembling that of PCL scaffolds. Additionally, micro-CT analysis reveals BG particles were homogeneously distributed throughout the scaffolds. Mechanical data suggested that PCL/45S5 and PCL/SrBG composite scaffolds have higher compressive Young's modulus compared to PCL scaffolds at similar porosity (∼75%). After 1 day in accelerated degradation conditions using 5M NaOH, PCL/SrBG, PCL/45S5 and PCL lost 48.6 ± 3.8%, 12.1 ± 1% and 1.6 ± 1% of the original mass, respectively. In vitro studies were conducted using MC3T3 cells under normal and osteogenic conditions. All scaffolds were shown to be non-cytotoxic, and supported cell attachment and proliferation. Our results also indicate that the inclusion of bioactive glass (BG) promotes precipitation of calcium phosphate on the scaffold surfaces which leads to earlier cell differentiation and matrix mineralization when compared to PCL scaffolds. However, as indicated by alkaline phosphatase activity, no significant difference in osteoblast differentiation was found between PCL/45S5 and PCL/SrBG scaffolds. These results suggest that PCL/45S5 and PCL/SrBG composite scaffolds show potential as next generation bone scaffolds.
authors.affiliation: Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, 4059 Brisbane, Australia.
authors.forename: Patrina S P
authors.initials: PS
authors.lastname: Poh
authors.forename: Dietmar W
authors.initials: DW
authors.lastname: Hutmacher
authors.forename: Molly M
authors.initials: MM
authors.lastname: Stevens
authors.forename: Maria A
authors.initials: MA
authors.lastname: Woodruff
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis / Q000378:metabolism; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001861:Bone Regeneration; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002516:Ceramics / Q000737:chemistry / Q000494:pharmacology*; D055119:Elastic Modulus; D005898:Glass / Q000737:chemistry; D008422:Materials Testing; D051379:Mice; D010006:Osteoblasts / Q000166:cytology; D023822:Tissue Engineering; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; C022107:Bioglass; C425330:bioactive glass 45S5; D000469:Alkaline Phosphatase