Developing a multifunctional gradient pore structure Janus membrane loaded with MB@ZIF-8 nanoparticles and hydroxyapatite for guided periodontal bone regeneration

The guided tissue regeneration (GTR) procedure has become an important process for the treatment of periodontal tissue regeneration, using the membrane as a mechanical barrier to generate a distance across the defect that subsequently allowing bone regeneration. Due to the complexity of periodontal microenvironment caused by bacterial infections, inflammation, and fibrous tissue penetration, the guided tissue regeneration membrane is required to have antibacterial and barrier functions. We developed a loaded methylene blue @ ZIF-8 and hydroxyapatite gradient thermoplastic polyurethane Janus membrane for antibacterial osteogenic and barrier. This Janus membrane with a porous gradient structure was prepared to use phase-conversion method. The rough layer facilitated cell growth and promoted periodontal bone regeneration, whereas the smooth layer isolated the growing fiber tissue.The rapid release of reactive oxygen species in the early stage and continuous release of zinc ions by methylene blue @ZIF-8 can achieve long-term synergistic antibacterial effect, with antibacterial rates of 84 % and 72 % against Escherichia coli and Staphylococcus aureus, respectively, which can effectively reduce the local inflammation caused by bacteria. In summary, we applied the Janus membrane to a rat periodontal bone defect model, and the membrane showed good surgical performance, barrier properties, osteogenic properties, and antibacterial effects, which could have broad application prospects in the treatment of periodontal bone defects.