Tri-layered functionally graded membrane for potential application in periodontal regeneration

Abstract

A novel tri-layered, functionally-graded chitosan membrane (FGM) with bioactive glass gradient (50%, 25%, and 0% wt.) was developed by lyophilization. A step-wise grading of chitosan, bioactive glass (BG), and Pluronic F127 was introduced into the membrane in which each layer has separate surface functions that play a role of guided tissue regeneration (GTR) membranes. The lower layer was designed to replicate alveolar bone and contains 50%wt. BG, the middle layer contains 25%wt. BG, while the upper layer was non-porous without BG and it did not support cell growth. Scanning Electron Microscopy (SEM) revealed that the lower FGM surface possessed a porous structure with embedded BG particles, while the upper surface was non-porous with interconnected architecture. The contact angle measurement confirmed that the surface with BG was hydrophilic (≈0⁰), while the opposite surface was hydrophobic (91⁰ ± 3.84⁰). Both osteoblast and fibroblast cells have maximum adhesion at contact angle <80°. Alamar blue assay revealed the biocompatibility of the MC3T3-E1 mouse pre-osteoblasts cells with these membranes in vitro. The cells attachment and proliferation was seen for lower surface, while no cells adhesion was observed for the upper layer. Additionally, the interaction of the tissue with these tri-layered membranes was also investigated in vivo. Hematoxylin and eosin staining revealed the biocompatible nature of these membranes. Altogether, these results indicated that due to the biocompatible nature of these membranes, they will be a good carrier of in vivo implantation.

Keywords: Animal studies; Bioactivity and biocompatibility; Functionally graded membrane; Guided tissue regeneration; MC3T3-E1; Pluronic F127.