Insights into the Prospective Aerogel Scaffolds Composed of Chitosan/Aramid Nanofibers for Tissue Engineering

As an emergent interdisciplinary subject, tissue engineering is widely used in the maintenance, repair, replacement, and reconstruction of the structure and function of cartilage, blood vessels, heart, skin, and liver. Tissue engineering includes three elements: seed cells, tissue engineering scaffolds, and tissue construction. Among them, tissue engineering scaffolds, especially porous scaffolds, play an important role. The support material should have ideal physical, chemical, and mechanical properties matching with the actual application, such as specific size and shape, an appropriate pore size, and appropriate porosity and surface properties. As a kind of natural biopolymeric linear polysaccharide, chitosan (CHi) has sterling properties including being nontoxic, nonirritant, biocompatible, bacteriostatic, and excellently hydrophilic. Aramid fibers (AF) belong to a class of synthetic fibers that are thermally stable, chemically stable, and highly temperature-resistant and have low mass and a long service life. Previous studies have demonstrated that bulk AF can be effectively split into aramid nanofibers (ANFs) via dissolution in a system of dimethyl sulfoxide (DMSO)/potassium hydroxide (KOH). Composite aerogels own a three-dimensional and pore-like structure with the advantages of light weight, high porosity, and large specific surface area, which are suitable for use in the field of tissue engineering. Addressed herein is the composite aerogel synthesized from CHi and ANFs using chemical crosslinking with glutaraldehyde (GA) for a tissue engineering scaffold, named ANFs/CHi/GA. The composite was characterized using Fourier transform infrared spectroscopy and X-ray diffraction. ANFs/CHi/GA was bacteriostatic with abundant cell adhesions and a uniform cell distribution. Cytotoxicity tests prove that the composite aerogel materials are nontoxic and the cells could proliferate greatly in their leaching solutions. Cells can adhere to and distribute well on the surface of the composite aerogel material, which is suitable for use in scaffold materials.