The eye drops progressively deliver the right amount of drug-infused nanoparticles to the surface of the eyeball over a period of five days before the body absorbs them. One weekly dose replaces 15 or more to treat the pain and irritation of dry eyes.
The nanoparticles stick harmlessly to the eye's surface and use only five per cent of drug normally required.
Shengyan (Sandy) Liu
"You can't tell the difference between these nanoparticle eye drops and water," said Shengyan (Sandy) Liu, a PhD candidate at Waterloo's Faculty of Engineering, who led the team of researchers from the Department of Chemical Engineering and the Centre for Contact Lens Research. "There's no irritation to the eye."
Dry eye syndrome is a more common ailment for people over the age of 50 and may eventually lead to eye damage. More than six per cent of people in the U.S. have it. Currently, patients must frequently apply the medicine three times a day because of the eye's ability to self-cleanse—a process that washes away 95 per cent of the drug.
"I knew that if we focused on infusing biocompatible nanoparticles with Cyclosporine A, the drug in the eye drops, and make them stick to the eyeball without irritation for longer periods of time, it would also save patients time and reduce the possibility of toxic exposure due to excessive use of eye drops," said Liu.
The research team is now focusing on preparing the nanoparticle eye drops for clinical trials with the hope that this nanoparticle therapy could reach the shelves of drugstores within five years.