Therapeutic Contact Lenses for Comfort Molecules

Abstract

Dry eye syndrome affects nearly 15% of the population and can cause extreme discomfort that interferes with quality of life. Current treatment options include delivering comfort agents such as hyaluronic acid (HA) to the eye via eye drops, but low bioavailability continues to be a barrier to effective treatment. We have designed a therapeutic hydrogel contact lens that can deliver HA to the eye at a therapeutic rate. Control over the release characteristics is improved through biomimetic imprinting, as functional monomers such as acrylamide,N-vinyl pyrrolidone and (diethylamino)ethyl methacrylate are added to the hydrogel structure. The diffusion coefficients of hyaluronic acid, a long chain molecule, through the hydrogel can be controlled by varying the number of added functional monomers that interact with the drug molecule through memory sites. There is an inverse correlation between the total %-by-mass of functional monomers added to the hydrogel and the diffusion coefficient. Increasing the variety of functional monomers lowered the diffusion coefficient 1.5 times more than including a single type of functional monomer, and 1.6 times more than hydrogel without added monomers. By optimizing the functional monomer content of the hydrogel, we can deliver hyaluronic acid to the eye at a constant therapeutic rate of approximately 6 micrograms per hour for 24 hours.