Porous Zirconia Scaffolds Functionalized with Calcium Phosphate Layers and PLGA Nanoparticles Loaded with Hydrophobic Gentamicin

Abstract

Implant-related infections are a worldwide issue that is considered very challenging. Conventional therapies commonly end up failing; thus, new solutions are being investigated to overcome this problem. The in situ delivery of the drug at the implant site appears to be more sufficient compared to systemic antibiotic therapy. In this study, we manufactured porous zirconia scaffolds using the foam replication method. To improve their overall bioactivity, they were coated with a calcium phosphate (CaP) layer containing antibiotic-loaded degradable polymer nanoparticles (NPs) obtained by the double emulsion method to achieve the antibacterial effect additionally. Encapsulation efficiency (EE) and drug loading (DL) were superior and were equal to 99.9 ± 0.1% and 9.1 ± 0.1%, respectively. Scaffolds were analyzed with scanning electron microscopy, and their porosity was evaluated. The porosity of investigated samples was over 90% and resembled the microstructure of spongy bone. Furthermore, we investigated the cytocompatibility with osteoblast-like MG-63 cells and antimicrobial properties with Staphylococcus aureus. Scaffolds coated with a CaP layer were found non-toxic for MG-63 cells. Moreover, the presence of antibiotic-loaded nanoparticles had no significant influence on cell viability, and the obtained scaffolds inhibited bacteria growth. Provided processes of fabrication of highly porous zirconia scaffolds and surface functionalization allow minimizing the risk of implant-related infection.

3D Printed Porous Zirconia Biomaterials based on Triply Periodic Minimal Surfaces Promote Osseointegration In Vitro by Regulating Osteoimmunomodulation and Osteo/Angiogenesis

“…Various surface-treatment methods, including coating, sandblasting, and acid etching, can enhance the surface roughness of zirconia implants to facilitate bone integration. , However, these surface modifications may induce microcracks in zirconia and eventually cause implant fracture . Porous zirconia implants have been recently demonstrated to promote bone integration, with their biological activity being highly influenced by porosity . The TPMS structure possesses an open, regular, and interconnected porous network that facilitates efficient mass transport, cell migration, and tissue formation.…”

Harnessing the Potential of PLGA Nanoparticles for Enhanced Bone Regeneration

“…As for hydrophilic drugs, a W/O/W double emulsion is needed to be encapsulated in PLGA [143,144]. Similarly, solid-in-oil-in-water emulsion (S/O/W) may be used to encapsulate drugs in their solid forms [116]. Marquette et al used (S/O/W) to encapsulate anti-TNF alpha into PLGA microspheres [119].…”

Harnessing the Potential of PLGA Nanoparticles for Enhanced Bone Regeneration

“…As for hydrophilic drugs, a W/O/W double emulsion is needed to be encapsulated in PLGA [ 144 , 145 ]. Similarly, solid-in-oil-in-water emulsion (S/O/W) may be used to encapsulate drugs in their solid forms [ 117 ]. Marquette et al used S/O/W to encapsulate anti-TNF alpha into PLGA microspheres [ 120 ].…”