title: Elastomeric and mechanically stiff nanocomposites from poly(glycerol sebacate) and bioactive nanosilicates.
abstract: Poly(glycerol sebacate) (PGS) has been proposed for tissue engineering applications owing to its tough elastomeric mechanical properties, biocompatibility and controllable degradation. However, PGS shows limited bioactivity and thus constraining its utilization for musculoskeletal tissue engineering. To address this issue, we developed bioactive, highly elastomeric, and mechanically stiff nanocomposites by covalently reinforcing PGS network with two-dimensional (2D) nanosilicates. Nanosilicates are ultrathin nanomaterials and can induce osteogenic differentiation of human stem cells in the absence of any osteogenic factors such as dexamethasone or bone morphogenetic proteins-2 (BMP2). The addition of nanosilicate to PGS matrix significantly enhances the mechanical stiffness without affecting the elastomeric properties. Moreover, nanocomposites with higher amount of nanosilicates have higher in vitro stability as determined by degradation kinetics. The increase in mechanical stiffness and in vitro stability is mainly attributed to enhanced interactions between nanosilicates and PGS. We evaluated the in vitro bioactivity of nanocomposite using preosteoblast cells. The addition of nanosilicates significantly enhances the cell adhesion, support cell proliferation, upregulate alkaline phosphates and mineralized matrix production. Overall, the combination of high mechanically stiffness and elastomericity, tailorable degradation profile, and the ability to promote osteogenic differentiation of PGS-nanosilicate can be used for regeneration of bone.
authors: Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, United States.
authors: Punyavee
authors: P
authors: Kerativitayanan
authors: Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, United States; Department of Materials Science and Engineering, Texas A&M University, College Station, TX 77843, United States. Electronic address: gaharwar@tamu.edu.
authors: Akhilesh K
authors: AK
authors: Gaharwar
mesh_terms: D000818:Animals; D041702:BALB 3T3 Cells; D018786:Bone Substitutes / Q000138:chemical synthesis*; D002448:Cell Adhesion / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation / Q000502:physiology; D019245:Compressive Strength; D003651:Decanoates / Q000737:chemistry*; D055119:Elastic Modulus; D005990:Glycerol / Q000031:analogs & derivatives* / Q000737:chemistry; D006244:Hardness; D008422:Materials Testing; D051379:Mice; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology*; D011108:Polymers / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D013314:Stress, Mechanical; D013718:Tensile Strength
chemical_list: D018786:Bone Substitutes; D003651:Decanoates; D011108:Polymers; D017640:Silicates; C469892:poly(glycerol-sebacate); D005990:Glycerol
keywords: Bone regeneration; Elastomer; Nanocomposites; Poly(glycerol sebacate); Two-dimensional (2D) silicates