Episodes of bone replacement are rising steeply worldwide due to acute trauma and disorders associated with obesity and aging. Oxidative stress at the bone defect site is the major cause of delayed bone regeneration process. Increased level of reactive oxygen species (ROS) is the primary cause of oxidative stress at the damaged site. The level of ROS increased due to tissue injury and surgical activities. One of the potential solutions to these problems is a bone tissue engineering-based scaffold that can scavenge the ROS levels and thus aids in faster bone healing. Cerium oxide (ceria) is known to have redox modulating behavior. 3D printed porous scaffolds fabricated from degradable polymers are a suitable choice for bone tissue engineering applications. Surface modification is known to enhance cell-material interactions and impart bioactivity. In the current study, porous poly (lactic acid) (PLA) scaffolds were developed using a fused filament fabrication (FFF) based 3D printing strategy. Further, PLA scaffolds were surface-decorated with ceria nanoparticles by the dip-coating method. SEM micrographs revealed a porous structure that remains unchanged after surface functionalization. Several physical, mechanical, and degradation characterization were carried out for fabricated scaffolds to study the effect of functionalization. Cell studies revealed that ceria functionalization is non-toxic. Additionally, results from the ROS study demonstrate that ceria surface functionalization can reduce oxidative stress levels in human mesenchymal stem cells (hMSCs). Osteogenesis study exhibited that functionalized scaffolds exhibit improved osteogenic differentiation potential. Transcriptional profiling analyzed by next generation sequencing revealed changes in the expression of several genes associated with inflammation and cell-material interaction. The ceria functionalized scaffold show enhanced antibacterial activity against <i>gram-negative</i> and <i>gram-positive</i> bacterial strains. These promising results suggest that surface decoration with ceria may have potential application for enhancing porous 3D printed PLA scaffolds for bone tissue engineering with ROS scavenging and antibacterial efficacy.

Surface functionalization of 3D printed scaffolds using ceria nanoparticle for bone tissue engineering

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.