Biomimetic Hierarchical Eggshell Membrane/Chitosan-Polycaprolactone Micro/Nano Fibrous Scaffold for Skin Tissue Engineering Applications

Design and fabrication of a scaffold that can fulfill the require-ments of tissue engineering is determined by interaction between cell and its microenvironment. The objective of the present work was to develop a mechanically stable, biocompatible, porous, non-immu- nogenic and cost-effective bilayered scaffold for skin tissue engineering (STE) applications. We have deployed microfibrous eggshell membrane (ESM), which has a rich source of collagen, growth factors and GAGs, along with nanofibers of chitosan/polycaprolactone (PCL). A randomly arranged nanofibrous mat of chitosan-PCL (CPL) was electrospun over the microfibrous ESM under optimum conditions and crosslinked with each other using glutaraldehyde. The topography of the 0.27 mm thick bilayered scaffold was studied by FE-SEM and AFM, while BET technique estimated the porosity. Successful crosslinking between the fibers of CPL (150 nm diameter) and ESM (1 m m diameter) in the scaffold was evident by FT-IR and XPS analyses, thus confirmed the bilayer structure. The matrix exhibited slow enzymatic degradation, 70% wettability, tensile strength of 11 MPa, good anti-microbial activity and thermal stability. In addition, excellent adhesion and proliferation of human dermal fibroblast (hDF) cells were observed through MTT and SEM studies. Electron micrographs showed a sheath like morphology of the hDF cells seeded onto the scaffold after 7 days of incubation. Further, the efficiency of cell entrapment and proliferation was evaluated using Rhodamine-DAPI, H&E staining and live/dead assays. The hierarchical nano/micro fibrous bilayer scaffold mimics epidermis/dermis of human skin and holds the promise for skin tissue engineering and other biomedical applications