Characterization of Tunable Poly‐ε‐Lysine‐Based Hydrogels for Corneal Tissue Engineering

A family of poly‐ε‐lysine hydrogels can be synthesized by crosslinking with bis‐carboxylic acids using carbodiimide chemistry. In addition to creating hydrogels using a simple cast method, a fragmented method is used to introduce increased porosity within the hydrogel structure. Both methods have created tunable characteristics ranging in their mechanical properties, transparency, and water content, which is of interest to corneal tissue engineering and can be tailored to specific cellular needs and applications. With a worldwide shortage of cornea donor tissue available for transplant and limitations including rejection and potential infection, a synthetic material that can be used as a graft, or a partial thickness corneal replacement, would be an advantageous treatment method. These hydrogels can be tuned to have similar mechanical and transparency properties to the human cornea. They also support the attachment and growth of corneal epithelial cells and the integration of corneal stromal cells. Promising corneal tissue engineering scaffolds are synthesized based on poly‐ε‐lysine hydrogels crosslinked with bis‐carboxylic acids using carbodiimide chemistry. A library of polymer chemistries is characterized for their physical and mechanical properties and their cytocompatibilty with human corneal cell types. Inspired by achieving biomimicry, the characterization outputs are compared with human corneal tissue properties reported in literature.