Located on the back of the eye, the retina is a layer of nerve cells that convert incoming light to electrical signals – allowing us to see. Now, scientists have developed a rudimentary artificial retina, that could conceivably one day restore sight to the blind.
Developed in a collaboration between Sweden's Linköping University and Tel Aviv University in Israel, the prototype device takes the form of a tiny metal ring with an ultra-thin circular film of photoactive material inside of it. A hundred times thinner than a single neuron, that material is made up of a sheet of gold studded with an array of microscopic pixels, each one smaller in diameter than the width of a human hair.
Those pixels are in turn composed of a cheap, non-toxic organic pigment that is commonly used in cosmetics and tattooing ink. When exposed to light, semi-conducting nanocrystals within it produce an electrical pulse. In lab tests, these pulses were found to instantaneously stimulate cultured primary neurons, along with the neurons in otherwise light-insensitive retinas.
The device works all on its own, without any external connectors. It is now hoped that a descendant of it could someday be surgically implanted in the eyes of people with damaged or defective retinas. The research was led by Linköping senior lecturer Eric Glowacki (pictured above), and is described in a paper that was recently published in the journal Advanced Materials.
For examples of other retinal replacements that are in the works, check out the work being done at the University of Oxford, Johns Hopkins University and the Hebrew University of Jerusalem.
Source: Linköping University