Our retinal prosthesis, referred to as a dye-coupled film, was developed by chemically coupling photoelectric dyes to the surface of a polyethylene film for restoring retinitis pigmentosa. However, the amount of coupled dye decreased during an implantation test in a monkey’s eye. For improving long-term durability, anion exchange from Br− to PF6−, BF4−, and bis(trifluoromethanesulfonyl)imide (TFSI−) was conducted. The long-term durabilities of the dye-coupled film–PF6−, –TFSI−, and –BF4− improved by 637, 215, and 48%, respectively, indicating that the dye-coupled film–PF6− exhibits the best long-term durability.
- Koichiro Yamashita
- Tenu Tanaka
- Tetsuya Uchida