Hydrogel contact lens could save wearers' vision
Caused by autoimmune diseases, chemical burns, or sometimes even as a side effect of eye surgery, corneal melting is an incurable disease that's a major cause of blindness. It could someday be treated using a contact lens, however, which is currently in the works.
The disease does indeed involve a "melting" of the cornea, and it occurs when a person's cornea-located immune cells uncontrollably start producing enzymes known as matrix metalloproteinases (MMPs). These enzymes are dependent on the presence of zinc ions, which they contain.
With this in mind, some existing treatments involve the injection of medications that bind with such ions within the MMPs, subsequently removing those ions and thus neutralizing the enzymes. Unfortunately, though, such pharmaceuticals also bind with zinc ions in other parts of the body, causing severe side effects.
Being developed at the University of New Hampshire, the contact lens would incorporate a hydrogel consisting of a polymer called poly(2-hydroxyetyl methacrylate) and an organic compound called dipicolylamine – the latter binds with zinc ions. In lab tests performed on extracted corneal tissue, this gel has been shown to deactivate the three major types of MMPs involved in corneal melting. And, if applied directly to the cornea via a contact lens, its effect should be limited to the eye.
The university's commercialization branch, UNHInnovation, has filed for a patent on the technology. A paper on the research was recently published in the journal ACS Biomaterials Science and Engineering.
Source: University of New Hampshire