Long wearing contact lenses, that encapsulate medicine for slow release, and are coated with sugar for comfort, are being developed by researchers at the Fraunhofer Institute for Applied Polymer Research IAP with Israeli and German partners.
When eye diseases are treated topically, often only about 5% of the drug has an effect on the eye tissue. It is hoped that the new contact lenses will act as a transport system for active substances in order to prolong the contact time of the drug with the tissue in the eye. This system could be used, for example, to relieve pain, improve wound healing and protect the cornea.
The goal of the German-Israeli research team is to coat the inside of the contact lens with liposomes that carry a drug and release it over time. However, the use of liposomes is not the only strategy for optimising these contact lenses.
Sugars play a key role in providing comfort by acting as a lubricant in various parts of the body, and in the eye’s mucous layer, they enable the eyelid to glide smoothly. For this reason, researchers at the Fraunhofer IAP have developed polymers with a high sugar content – called glycopolymers – that coat the entire surface of the contact lens. These glycopolymers will also perform as structural components of the liposomes carrying the drug.
The three-year project, which has received funding of around one million euros from the German Federal Ministry of Education and Research (BMBF) will run until July 2021. The researchers must ensure functionality and that all components are biocompatible. They also need to make sure that the glycopolymer can be produced in large quantities at a price that allows the contact lens to be competitively marketed.
