Retinal Film Detects Light

A new light-sensitive nanotube-based film could pave the way to more flexible and durable retinal implants.

Nov 13, 2014
Jef Akst

A flexible film that can react to lightAMERICAN CHEMICAL SOCIETYYael Hanein Tel Aviv University and colleagues have developed a wireless film, built from semiconductor nanorods and carbon nanotubes, that they say could improve existing retinal implants. Testing the device in chick retinal tissue that normally does not respond to light, the researchers confirmed that the film not only absorbed light, but sparked neuronal activity in response.

“Photocurrent, photovoltage, and fluorescence lifetime measurements validate efficient charge transfer between the nanorods and the carbon nanotube films,” they wrote in their paper, published last month (October 28) in Nano Letters. “Successful stimulation of a light-insensitive chick retina suggests the potential use of this novel platform in future artificial retina applications.”

Retinal implants that can translate sensory input into neural activation in the vision-impaired have become an increasingly popular way to fight loss of sight, in particular that caused by macular degeneration. (See “The Bionic Eye,” The Scientist, October 2014.) The problem that Henein’s team saw with existing devices is that they have metallic parts, cumbersome wiring, or low resolution, according to an American Chemical Society press release. The team’s new device is wireless and completely flexible. “In comparison with other technologies, the researchers conclude theirs is more durable, flexible and efficient, as well as better able to stimulate neurons,” the ACS press release read.