Kerativitayanan, Punyavee (2015-12). Bioactive and Elastomeric Scaffolds: A Growth-Factor-Free Approach for Bone Tissue Engineering. Master's Thesis.
Thesis
Bone is the second most transplanted organ following blood, and significant advances have been made in developing synthetic bone graft substitutes and scaffolds. However, there remains a critical need for osteoinductive scaffolds with mechanical functionality for bone tissue engineering at load-bearing sites. Here, we reported nanocomposite scaffolds of elastomeric poly(glycerol sebacate)(PGS) and osteoindictive nanosilicates, fabricated via salt-leaching method. Nanosilicates are ultrathin nanomaterials reported to 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 nanosilicates to PGS matrix resulted in enhanced physical integrity as well as increased mechanical strength and toughness. Remarkably, elastomeric properties of the scaffolds were not compromised, providing a load-transducing environment for bone regeneration. PGS/nanosilicates scaffolds supported cell proliferation and promoted cell spreading. The addition of nanosilicates upregulated osteogenic differentiation of seeded preosteoblasts in a concentration-dependent manner as evidenced by increased ALP activity and matrix mineralization, even when cultured in normal growth media without any osteogenic factors. All in all, the combination of elasticity and tunable stiffness, tailorable degradation profiles, and the ability to promote osteogenic differentiation of the scaffolds offered a promising growth-factor-free approach for bone tissue engineering.
