Functionalized Asymmetric Poly (Lactic Acid)/Gelatin Composite Membrane for Guided Periodontal Tissue Regeneration

Aim: Periodontitis is caused by chronic gingival inflammation and affects a large population in the world. Although guided tissue regeneration (GTR) therapy has been proven to be an effective treatment, the deficiency in the symmetrical design of all the GTR membrane in the market leaves large space for improvement. Therefore, we designed a novel asymmetrical bi-layer PLA/gelatin composite membrane for treating periodontitis. Methods: The PLA side was fabricated by electrospinning with metronidazole (MNA) pre-mixed with the PLA solution. The gelatin side containing bioglass (BG) 45S5 was fabricated with freeze-drying process and cross-linked with PLA membrane. The bio-compatibility of the membrane was evaluated in vitro using NIH3T3 cells. The releasing of MNA was measured by spectrophotometer. The bioactivity of the membrane was evaluated by hydroxyapatite (HA) deposit and determined by FTIR spectrometer. The ionic concentration of Ca2+ and was measured by ICPOES. The expression of the osteogenesis makers was determined by qRT-PCR. Results: The bi-layer PLA/gelatin composite membrane is biocompatible and bioactive. The releasing of MNA can rapidly reach the anti-bacterial effective concentration. Interestingly, the incorporation of MNA modulated the degradation rate of PLA scaffold to meet the requirement of tissue regeneration. Meanwhile, the embedding of the BG powder in the gelatin porous layer provided a favorable Ca2+ and ion environment for the regeneration of the alveolar bone tissue. Conclusions: Taken together, this bi-layer GTR membrane is closer to the physiological structure of the periodontal. The addition of MNA and BG makes it more powerful in treating periodontitis. Moreover, this research provides an example of biomimetic design in fabricating biomaterial for clinical applications.