Artificial photoreceptors that can restore the visual response in blind mice are reported in a study published online in Nature Communications.

The use of prosthetics to help restore vision could be used to treat degenerative diseases such as retinitis pigmentosa or macular degeneration, which untreated, leads to loss of vision and blindness. Current prosthesis devices require implanting a light detecting array that detects signals from a video-capture camera.

Jiayi Zhang and colleagues report the development of gold nanoparticle coated titanium dioxide nanowires that function as artificial photoreceptors. The wires generate a voltage when exposed to light, which can then be passed to neighbouring neurons and help restore the visual response in blind mice. The array is able to restore electrical readout and pupil dilation when the mice are exposed to green, blue and ultraviolet light. Importantly, the implant was well tolerated by the mice and stably active for up to eight weeks.

The use of implanted prosthetics to treat degenerative eye diseases could potentially be applied to human patients one day. The work could lead to the design of better prosthetics that do not require external power sources and are capable of colour vision. This could open up new treatment options for people at risk of long-term visual degeneration.