Retinal blindness in several forms afflict millions of people. Scientists would like to create implantable microelectronic prostheses to help these patients see better. Researchers at the University of Alabama, Huntsville, have come up with a series of waterproof polymer coatings that both protect the prostheses and the sensitive eye tissue of the patient. The research was presented on March 30 at the American Chemical Society national meeting in Anaheim.
Retinal implants could help millions of people with ocular disease get back some of their vision. It’s not easy, however, to create a device that can send electrical signals from a camera to an electrode array in the eye. A drop of water gets into the electronics and poof! The electronics short out.
To address the issue, Carmen Scholz’s team is studying a number of protective polymeric coatings. The problem is that the material has to be biocompatible as well as waterproof. Even if a thin layer of damaged tissue forms in reaction to the polymer, the scar could block the device’s weak electrical signals.
As Aaron Rowe reported in a Chemical & Engineering News article, Scholz’s team started off two polymers and two other substances that they tested in pig eyes. Amorphous aluminum oxide and polyvinyl pyrrolidone caused severe irritation, but polyethylene glycol and diamond-like carbon performed better. Now the researchers are focusing on creating polymers out of polyethylene glycol and amino acid-based polymers. They are also testing to see if polyoxazoline can replace polyethylene glycol.
Rajendrani "Raj" Mukhopadhyay is a science writer and editor who contributes news stories and feature articles on scientific advances to a variety of magazines. Raj holds Ph.D. in biophysics from Johns Hopkins University.