Porous Titanium/SF Sponge Composite Scaffold with Loads of Gentamicin and Small Extracellular Vesicles to Improve Antibacterial and Osteogenesis Properties

Additive manufacturing has been widely used for producing porous titanium orthopedic implants. However, the higher surface area inherent to porous structures increases the risk of bacterial colonization. In this work, composite scaffolds with dual functions of the antibacterial and osteogenesis promotion properties are developed. The porous titanium is fabricated using a selective laser melting process to provide mechanical support. Silk fibrin (SF) sponge-loading gentamicin and extracellular vesicles (EVs) are prepared in the pores of the porous titanium. The developed composite scaffolds are investigated for their antibacterial and osteogenesis effects. The samples exhibit well antibacterial activity against Escherichia coli. The samples also show good cytocompatibility, effectively promoting the adhesion and proliferation of the bone marrow mesenchymal stem cells (rBMSCs). EVs significantly promote the expression of osteogenesis-related genes in rBMCSs and the superior extracellular matrix mineralization reveals that EVs have a remarkable role in enhancing osteogenic differentiation. Therefore, the composite scaffolds with dual functions of antibacterial and osteogenesis promotion properties have excellent potential for orthopedic implant applications. In this paper, a porous titanium scaffold is fabricated by additive manufacturing. Silk fibrin sponge-loading gentamicin and extracellular vesicles are prepared in the pores of the porous titanium. This study confirms that the scaffold has both antibacterial and bone-promoting effects. image