Initially study with rats
Injection with nanoparticles enables night vision
06/20/2022 11:54 am
Night Vision Without Night Vision Devices: What seems like science fiction could soon become a reality. Researchers have been able to make mice see in the near-infrared range – by injecting nanoparticles into their eyes. Similar nanoparticles could also help people with poor vision and eye diseases.
Humans can see light only in limited frequencies. Low frequencies like infrared are not visible to our eyes because the photoreceptors are not responsive to them. Technologies such as night vision goggles make this frequency range visible, for example by converting near-infrared into visible light. But it can work without it, as one study shows.
Scientists at the University of Massachusetts Medical School and the University of Science and Technology of China have developed nanoparticles that rats can use to see at night. for their study, Expert magazine “SAIL” Visible, Gang Han’s team injected the nanoparticles under the rodents’ retinas. The bloodstream then carries the nanoparticles to the eye. There, these so-called nano-antennas connect to photoreceptors, that is, cells that are responsible for the perception of light. This allows the eye to react to near-infrared light, which normally would not trigger a signal.
According to the study, a series of experiments showed that rats could indeed see in this frequency range: if, for example, near-infrared light is shone into the eye, only the injected rats’ pupils constrict. , whereas the pupils of the control group did not respond. In the injected rats, near-infrared light also activated the visual cortex, which is responsible for visual perception in the brain. Further investigation also revealed that the ability to see at night is apparently a loss of sight. impaired under visible light.
Night vision without complicated equipment
The anchored particles expand the visible light spectrum in such a way that animals can see the near-infrared from the non-visible range, the researchers wrote. The brain then processes this information and interprets it as an image. “This is done without the help of complex equipment,” says the study. After the injection, the effect lasted for two months.
Furthermore, this procedure appears to be relatively safe. Side effects were rare in test animals. According to scientists, some animals had a cloudy cornea after the injection, but it disappeared on its own within a week.
“That’s why we believe this technique works for the human eye as well,” said study lead author Tian Xu. “In our experiment, the nanoparticles absorbed infrared light at a wavelength of 980 nanometers and converted it into light at 535 nanometers.” Light with a wavelength of 535 nanometers is visible to the human eye and is perceived as green.
According to the researchers, it is conceivable that nanoparticles could be used not only to improve human vision, but also to treat visual impairment and eye diseases. “With this research, we have greatly expanded the applications of nanoparticle technology. With a little help, we can have the ability to see all the hidden information of NIR and IR radiation in the universe that is not visible to our naked eye.” is,” summarizes study author Gang Han.
