A team of researchers from Yonsei University, Severance Hospital, and Gangnam Severance Hospital has developed a high-safety, liquid metal-based soft artificial retina.

This innovative technology promises to restore vision to patients blinded by retinal diseases, including retinitis pigmentosa and macular degeneration.

Traditionally, the treatment for severe retinal conditions leading to blindness has involved connecting an artificial retina device directly to the retina or the brain.

However, this process has been plagued by challenges as the insertion of metal electrodes into the soft neural tissues of the retina or brain often results in damage, inflammation, and scarring, which can eventually disrupt the transmission of electrical signals between the neural tissue and the electrode.

To resolve this issue, the team, led by Professors Byeon Suk-ho of the Department of Ophthalmology at Severance Hospital, Park Jang-ung of the Department of Advanced Materials Engineering at Yonsei University, and Lee Jun-won of the Department of Ophthalmology at Gangnam Severance Hospital, newly developed a soft artificial retina.

The retina overcomes these limitations by utilizing biocompatible liquid metal for its 3D electrodes.

Unlike the solid metal-based electrodes used in previous devices, the liquid metal electrodes mimic the softness of retinal tissue, minimizing damage and ensuring closer contact with the curved surface of the retina.

The team verified the effectiveness of the soft artificial retina in mouse models blinded by retinal degeneration.

When exposed to light, parts of the retina implanted with the device produced signals approximately four times stronger than the areas not exposed to light, indicating a restoration of visual function.

Notably, the 3D liquid metal electrodes outperformed flat electrodes made of the same material in signal transmission efficiency by about two times, and the new device did not trigger any immune response or inflammation, unlike its solid metal counterparts.

"The artificial retina device using liquid metal 3D electrodes significantly reduces damage to retinal tissues and ensures precise and stable contact with the retina's irregular surface compared to traditional hard metal artificial retinas,” Professor Byeon said. “This research paves the way for the development of customized artificial retinas for patients with blindness."

The results of the research were published in Nature Nanotechnology.