For years, treating scratches and burns to the eyes has usually involved dropping medicine onto the eyes several times a day, sometimes for weeks — a treatment that lends itself to missed doses and other side effects. But scientists are now reporting in the journal ACS Nano a novel, drug-releasing wafer that patients can put directly on their affected eyes just once a day. The team says the device works better than drops and could help patients recover faster.
Ghanashyam Acharya, Stephen C. Pflugfelder and colleagues point out that eye injuries are a major cause of blindness worldwide. In the U.S., about 2.5 million people suffer such an injury every year. But typical eye drop therapies are not very efficient. Blinking and tears clear the medicine quickly from the eyes, so patients have to apply drops several times a day. But this frequency boosts the risks for side effects, including inflammation and blurred vision, and makes it likely that patients will miss doses. Researchers have tried many approaches to address these problems, but none so far have worked well.
In a new approach, Acharya’s team developed a clear, round film — which for humans would be about one-tenth the size of a typical contact lens — embedded with tiny pockets that can hold and release medicine slowly over time. The film then dissolves completely. In mice, the wafer was twice as effective as eye drops and didn’t cause inflammation that can lead to side effects. The team concludes that the wafer could be used to treat eye injuries and other conditions such as chronic dry eye and glaucoma.
Ocular Drug Delivery Nanowafer with Enhanced Therapeutic Efficacy, DOI: 10.1021/nn506599f
The authors acknowledge funding from the U.S. Department of Defense.