A new material that converts visible light into infrared light
Scientists at Columbia University, in collaboration with researchers at Harvard University, have successfully developed a chemical process that converts visible light into infrared light, allowing the innocuous radiation of infrared light to penetrate living tissue and other materials. Avoid damage from high intensity light.
Their research was published in the January 17 issue of Nature.
“The results are exciting because we are able to perform a series of complex chemical transformations that often require the use of non-invasive infrared sources to produce high-energy visible light,” said Tomislav, a professor of chemistry at Columbia University and co-author of the research. Rovis said. “A lot of potential applications can be imagined, such as some application barriers that are difficult to control. For example, the study is expected to enhance the range and effectiveness of photodynamic therapy, and the full potential of photodynamic therapy in treating cancer has not yet been realized.”
The team includes Luis M. Campos, associate professor of chemistry at Columbia University, and Daniel M. Congreve, from the Rowland Institute at Harvard University, who conducted a series of experiments using a small number of new compounds that mediate electron transfer between molecules under light stimulation. They will react more slowly or not at all without light.
Their method, called triple fusion upconversion, involves a series of processes that essentially fuse two infrared photons into one visible photon. Most technologies only capture visible light, which means the rest of the solar spectrum is wasted. The triple fusion upconversion captures low-energy infrared light and converts it into visible light, which is then absorbed by the solar panel. Visible light is also easily reflected by many surfaces, while infrared light has a longer wavelength and can penetrate dense materials.
“Through this technology, we were able to adjust the infrared light to the required, longer wavelengths, allowing us to non-invasively pass through a wide variety of obstacles such as paper, plastic molds, blood and tissue,” Campos said. . The researchers even pulsed through two bacon wrapped around a flask.
Scientists have long tried to solve the problem of how visible light can penetrate the skin and blood without damaging the internal organs or healthy tissues. Photodynamic Therapy (PDT), which is used to treat certain cancers, uses a special drug called a photosensitizer that is triggered by light to produce highly reactive oxygen that kills or inhibits the growth of cancer cells.
Current photodynamic therapy is limited to the treatment of topical or superficial cancers. “This new technology can bring PDT into areas that the body could not previously enter,” Rovis said.
"Compared to the use of drugs that cause malignant cells and healthy cell death to poison the entire body, the process described herein can be viewed as a non-toxic drug that binds to infrared light, which can selectively target tumor sites and illuminate cancer cells. ”
This technology can have far-reaching effects. Infrared light therapy can help treat many diseases and conditions, including traumatic brain damage, damaged nerves and spinal cord, hearing loss, and cancer.
Other potential applications include remote management of chemical warehouses, solar power and data storage, drug development, sensors, food safety methods, moldable bone analog composites, and processing of microelectronic components.
Researchers are currently testing photon upconversion techniques in other biological systems. “This opens up an unprecedented opportunity to change the way light interacts with living things,” Campos said. “In fact, we are currently using up-conversion technology for tissue construction and drug delivery.”