Are nanoparticles the key to more effective eye drops?

Researchers at the University of Reading, UK, report that they have discovered a potential way of making eye drops more effective.

The researchers report in Molecular Pharmaceutics that they have developed nanoparticles that could attach to the cornea and resist being washed out by tear fluid for an extended period of time. If these nanoparticles are loaded with a drug, the researchers say, their longer attachment to the cornea would ensure more medicine penetrates the eye and improves drop treatment.

Professor Vitaliy Khutoryanskiy, from the University of Reading's School of Pharmacy, said, "Treating eye disorders is a challenging task. Our corneas allow us to see and serve as a barrier that protects our eyes from microbial and chemical intervention. Unfortunately this barrier hinders the effectiveness of eye drops. Many medicines administered to the eye are inefficient, as they often cannot penetrate the cornea barrier. Only the very small molecules in eye drops can penetrate [a] healthy cornea.

"Our research in bovine models showed that penetration of small drug molecules could be improved by adding enhancers such as cyclodextrins," Prof. Khutoryanskiy added. "This means eye drops have the potential to be a more effective, and a more comfortable, future treatment for disorders such as age-related macular degeneration."

In the same paper, the researchers revealed insights into how the structure of the cornea prevents various small and large molecules, as well as nanoparticles, from entering into the eye, and examined the effects any damage to the eye would have in allowing these materials to enter the body.