(601c) Bioactive Nanoengineered Hydrogels for Bone Tissue Engineering: A Growth-Factor-Free Approach

Despite bone’s impressive ability to heal after traumatic injuries and fractures, a significant need still exists for developing strategies to promote healing of non-union defects. To address this issue, we developed collagen-based hydrogels containing two-dimensional (2D) nanosilicates. Nanosilicates are ultrathin nanomaterials with a high degree of anisotropy and functionality that results in enhanced surface interactions with biological entities compared to their respective three-dimensional counterparts. The addition of nanosilicates resulted in a four-fold increase in compressive modulus along with an increase in pore size compared to collagen-based hydrogels. In vitro evaluation indicated that the nanocomposite hydrogels are capable of promoting osteogenesis in the absence of any osteoinductive factors. A three-fold increase in alkaline phosphatase activity and a four-fold increase in the formation of the mineralized matrix was observed with the addition of the nanosilicates to the collagen-based hydrogels. Overall, these results demonstrate the multiple functions of nanosilicates conducive to the regeneration of bone in non-union defects, including increased network stiffness and porosity, injectability and enhanced mineralized matrix formation in a growth-factor-free microenvironment.