Fabrication and evaluation of electrospun PCL–gelatin micro-/nanofiber membranes for anti-infective GTR implants

Infection is the major reason for GTR/GBR membrane failure in clinical applications. In this work, we developed GTR/GBR membranes with localized drug delivery function to prevent infection. Hierarchical membranes containing micro- and nano-fibers were fabricated. The effects of the incorporation of gelatin and loading content of metronidazole (MNA) (0, 5, 10, 20, 30, and 40 wt% polymer) on the properties of the electrospun membranes were investigated. The interaction between PCL and MNA was identified by molecular dynamics simulation. MNA was released in a controlled manner, and the antibacterial activity of the released MNA remained. The incorporation of gelatin and MNA improved the hydrophilicity, biocompatibility, and in vitro biodegradation rate of PCL nanofibers. The electrospun membranes allowed cells to adhere to and proliferate on them and showed excellent barrier function. The membrane loaded with 30% MNA had the best comprehensive properties. Subcutaneous implantation results demonstrated that MNA-loaded membranes evoked a less severe inflammatory response than pure PCL nanofibers. These results demonstrated the potential of MNA-loaded membranes as GTR/GBR membranes with antibacterial and anti-inflammatory functions for biomedical applications.