Ultra-powerful graphene retina could one day restore sight to millions

20 Aug 2018

Image: Natalia_Arefieva/Shutterstock

Graphene’s potential is being talked about again, and this time it could help restore the eyesight of millions of people.

The World Health Organization estimates that about 253m people across the world live with some form of vision impairment, many of which are caused by chronic eye diseases.

However, unlike many other medical conditions, these effects can be prevented or completely reversed in 80pc of cases.

This is largely to do with a lack of access to readily available medical services in some of the poorest countries, but a new artificial retina could one day drastically change this.

A world first

Presenting its findings to the American Chemical Society, an international team of researchers said it has successfully developed and tested the world’s first ultra-thin retina from the ‘wonder material’ known as graphene.

The flexible device could be implanted within a person’s eye and, with a few modifications, could be used to track heart and brain activity when placed in other parts of the body.

The device is based on how the natural retina works, whereby it contains specialised photoreceptor cells known as cones and rods.

Converting incoming light into nerve signals, these impulses travel into the brain via the optic nerve and are then decoded into visual images.

In diseases such as macular degeneration and diabetic retinopathy, retinal tissue is destroyed as they take hold, leading to vision loss or complete blindness.

With no known cure, researchers have worked to develop retinal implants to bypass the damaged tissue, but existing silicon-based devices are rigid, flat and fragile. On top of that, they often produce blurry or distorted images to the detriment of the user.

‘A very exciting starting point’

This latest device, meanwhile, used graphene and molybdenum disulphide as well as thin layers of gold, alumina and silicon nitrate to create a flexible, high-density and curved sensor array.

Resembling a flattened football, the device can conform itself to the shape of a natural retina without mechanically disturbing it.

“Although this research is still in its infancy, it is a very exciting starting point for the use of these materials to restore vision,” said Nanshu Lu of the research team.

Looking to the future, the team is aiming to integrate the technology into mechanically and optically imperceptible electronic tattoos that are laminated on the skin surface to gather real-time health information.

Colm Gorey was a senior journalist with Silicon Republic