A new tissue‐polymer hybrid drug delivery system for artificial corneas

Abstract

Abstract Purpose We developed and evaluated a new hybrid tissue‐polymer drug delivery system using lyophilized cornea and synthetic hydrogel. The feasibility of this system as a carrier and a drug delivery system for an artificial cornea (Boston Keratoprosthesis) was evaluated in vitro while non‐modified cornea tissue was used as a control. Methods Corneal tissue from the eye bank was first lyophilized. The tissue‐polymer hybrid was synthesized by reconstituting the lyophilized cornea in a norfloxacin‐loaded hydrogel solution followed by polymerization. Four different tissue‐hydrogel compositions of varying hydrophobicity were synthesized and characterized over one month for the swelling and the drug release profile. Unmodified cornea tissue was used as a control. The mechanical strength and suture characteristics of the hybrid system and unmodified cornea were evaluated as a carrier for Boston K‐pro using an artificial anterior chamber. Results Both the hybrid‐system and the control show excellent mechanical properties as carriers for the Boston K‐pro. They withstood similar challenges of intrachamber pressures (50‐70 mmHg) for wound stability. In vitro drug release analysis demonstrates a longer and more controlled drug release profile for the hybrid system as compared to the control. The most hydrophobic hybrid construct shows a release that is above the Minimum Inhibitory Concentration 90 of Staphylococcus epidermidis for the first two days. Conclusion The new hybrid tissue‐polymer system shows sufficient mechanical stability to serve as a carrier for the Boston K‐pro. This system has the potential to simplify storage and distribution of donor tissue as a carrier for artificial cornea in developing countries where donor tissue is otherwise not readily available.