Conversion of near-infrared (NIR) light into the visible light through a nanoparticle technology has now increased the possibility of built-in night vision in humans. Tests were successfully carried out on mice by the researchers from the University of Massachusetts Medical School (UMMS).
A normal human can see the visible light of 400 and 700nm wavelength, while near-infrared (NIR) light has a longer wavelength of 750nm to 1.4 micrometers which is out of the reach of the human eye. To see NIR radiations emitted by organisms in the dark, bulky and inconvenient instruments like thermal imaging cameras are used. But most probably the need for these instruments is ultimately going to rip off.
This week on 27th August, in the American Chemical Society (ACS) fall 2019 National Meeting & Exposition which was held in San Diego, researchers from the UMMS presented their findings related to this innovative technology. Now, the scientists have revealed advancement in making the varieties of nanoparticles for human applications.
A Ph.D. student at UMMS and the project’s principal investigator, named Gang Han said, “When we look at the universe, we see only visible light. If we had a near-infrared vision, we could see the universe in a whole new way. We might be able to do infrared astronomy with the naked eye or have night vision without bulky equipment.”
Experiments were conducted on Mice to come up with this Research
Firstly, upconversion nanoparticles, UCNPs were designed by Han and its team which has the ability of “upconversion” of NIR into visible light. This is done by converting the low energy photons into high energy photons emitting green light, making the human eye capable to see in the dark.
As the rats are remarkably similar to humans so Han and its colleagues also performed experiments on mice. UNCPs composed by rare earth metals are injected into the mice of eyes. Several behavioral and psychological tests are performed to find out whether mice can process the NIR light to see in the dark.
Mice trained to swim in a Y-shaped tank towards visible light having triangular shape by researchers. A shallow platform there made the mice easily climb on to get out of the water. Similarly, a lit circle denoted a branch without a platform. After the mice were trained well, the visible light was then replaced with NIR.
The mice with the particle injection could see the triangle clearly and swim to it each time, but the mice without the injection could not see or tell the difference between the two shapes.
Progressive efforts are being done on nanoparticles to make them safe for human application:
Although, after this experiment, no negative effects were reported even UNCPs endured in mice’s eyes for about 10 weeks. Han said, “The UCNPs in our published paper are inorganic and there are some drawbacks there. The biocompatibility is not completely clear and we need to improve the brightness of the nanoparticles for human use.”
So, the team is now considering replacing the rare-earth elements with organic dyes to make this emerging technology completely safe for human limiting even the little doubt of negative effect. Moreover, organic dyes have improved properties and fewer side effects.
“We’ve shown that we can make organic UCNPs with much-improved brightness compared with the inorganic ones,” said Han.
Nanotechnology and Super dogs:
In addition to this, Han and its team making the next plan to test this technology on dogs. “If we had a super dog that could see near-infrared light, we could project a pattern onto a lawbreaker’s’ body from a distance, and the dog could catch them without disturbing other people,” he said.
Above all, nanotechnology is emerging as a revolutionary breakthrough in different fields of science and technology to benefit the human being. Scientists are making stunning inventions in an expected and unexpected way.