3D Printed 13-93B3 borate bioactive glass/hydroxypropyl methyl cellulose/gelatin scaffolds with cerium oxide submicrometric particles for potential bone regeneration

In this study, a novel HPMC/gelatin composite scaffold was prepared by incorporating 13-93B3 borate bioactive glass (BBG) microparticles and cerium oxide (CeO₂) submicrometric particles as a discrete phase, enabling higher ceria loadings without disrupting the bioactive glass chemistry. Composite hydrogel inks containing 5 wt% BBG microparticles and up to 20 wt% CeO₂ submicrometric particles were successfully extrusion-printed into porous scaffolds with interconnected pore architecture. CeO₂ incorporation preserved printability and mechanical strength while significantly enhancing scaffold deformation ability. Degradation behavior was tunable, with BBG microparticles reducing swelling and CeO₂ submicrometric particles modulating water uptake and pH evolution. BBG microparticles and CeO₂ submicrometric particles synergistically promoted apatite formation following 7 days of SBF incubation. In vitro studies using MC3T3-E1 pre-osteoblasts confirmed high cytocompatibility and Alizarin red study showed enhanced mineralization in CeO₂-containing scaffolds. Additionally, BBG and CeO₂ incorporated scaffolds exhibited strong antibacterial activity against Staphylococcus aureus and Escherichia coli. Overall, this multifunctional scaffold platform demonstrates promise for bone tissue engineering applications.