Delivering anesthesia via contact lenses

Eye drops are so 1.0. Not only can they be messy and inconvenient to apply, they deliver medicine to treat dryness and other issues in imprecise volumes so quickly that they need to be reapplied every few hours.

And for those applying eye drops after laser eye surgery--when the eyes are especially tender--they can be a real pain.

Which is why researchers at the University of Florida are working to design contact lenses already helpful in protecting the eyes post-surgery that can extend the release time of anesthesia to help with this post-surgery pain.

The trick, chemist Anuj Chauhan and colleagues report in the journal Langmuir, is vitamin E.

By adding "highly hydrophobic" vitamin E aggregates to silicone hydrogel lenses for distribution of three commonly used anesthetics post-surgery, they found that the aggregates acted as barriers; by not interacting so readily with water on the surface of the eye, this barrier was able to extend the release time of the anesthetics from just a few hours to multiple days.

This isn't the first time contact lenses have been used to distribute drugs, or even that vitamin E has been used to slow the release of drugs in lenses. But it is an early sign of success for the specific anesthetics used following laser eye surgery.

The researchers suggest this discovery could solve two problems at once, providing not just the dispersal of drugs over longer periods of time, but also acting as bandage contact lenses to protect the eyes in the days following surgery.