Study shows how nanoparticles can expand eyesight
An American-Chinese research team recently successfully tested a new substance that makes it possible to see in the dark. After a single injection, the mice in which the substance was tested were able to see infrared for up to ten weeks. After injection, tiny nanoparticles change the wavelength at which the eye perceives light, thus enabling vision in the dark. The research team also thinks it can be used in humans.
Researchers from the University of Science and Technology of China and the University of Massachusetts Medical School have developed a substance that confers night vision ability. It sounds like it came straight out of a Marvel comic, but it's actually the latest high-tech. The injected nanoparticles expanded the spectrum of visible light so that the mice could see infrared light after the syringe. The research results were recently presented in the renowned journal "Cell".
Why we can't see anything in the dark
The human eye as well as the eye of a typical mammal can only perceive light that moves in the spectrum between about 400 to 700 nanometers. “However, this is only a small percentage of the entire electromagnetic spectrum,” the researchers explain. The human eye is unable to see longer-wave light like infrared light. Night vision glasses make it possible to perceive such a light spectrum. This is where the research team started. Using microscopic nano-antennas, they temporarily changed the rodents' eyes so that they could perceive longer-wave light.
Let there be light
The researchers explain the process: The mice are injected with protein using tiny nano-antennas. The proteins transfer the attached nanoparticles to the eye, where they anchor themselves to the photoreceptors of the eye. These cells are responsible for the perception of light. The anchored particles expand the spectrum and ensure that near infrared (NIR) can be perceived from the invisible range. This information is passed on to the brain and interpreted as an image. "This happens without the help of complicated devices," says the study team.
Green instead of black
"In our experiment, the nanoparticles absorbed infrared light at a wavelength of 980 nanometers and converted it into light with 535 nanometers," explains Jin Bao from the Chinese research team. This spectrum is visible to the human eye and is perceived as a green color.
Rare side effects
So far, the researchers have found only rare and weak side effects of the injection in the mice. In some rodents, the corneas of the eye clouded. However, this cloudiness disappeared again within a week.
Can it also be used in humans?
"We believe that this technology will also work for the human eye," emphasizes Professor of Biochemistry and Molecular Pharmacology Dr. Gang Han in a press release on the study results. He sees not only applications in the expansion of human eyesight, but also therapeutic solutions for people with poor eyesight.
Breakthrough in nano research
"With this research, we have extensively expanded the applications of nanoparticle technology," said the professor. The researchers see a large number of possible areas of application, ranging from the exploration of neuronal networks in the brain to the support of eyesight. "With a little help, we may have the ability to see all of the hidden information about NIR and IR radiation in the universe that is not visible to our naked eyes," the biochemist concludes. (vb)