This effectively prevents one of the biggest problems in the production of fluorescent materials – the tendency for fluorescent dyes to fade and change color when converting from a liquid to a solid state. And the work is not done just for entertainment.
“These materials have potential applications in any technology that requires optical properties to design optical properties, including solar energy harvesting, bioimaging, and lasers,” said chemist Amar Flood of the University of Indiana.
“Beyond these, there are interesting applications that include centrifuged light to capture more of the solar spectrum in solar cells, light-autonomous materials used for information storage and photochromic glass, and 3D display technology. Circulars are polarized luminescence. ”
Fluorescent molecules absorb light, and then re-emit it for longer periods of time at lower energy wavelengths. Found beyond the highlighters you used on your school notes, they have many practical applications in cell research, from fluorescent biomarkers to OLED technology.
Although, to date, over 100,000 fluorescent dyes have been developed, almost none can be anticipated and reliably mixed; Creating solid fluorescent materials is equally challenging. When the dyes turn into a solid, they undergo quenching (a dimming in brightness), their colors change, and their quantum efficiency declines.
It is not that chemists do not understand why this happens. This is a well understood phenomenon known as exciton coupling. When the colors are converted into a solid, they are packed together, which results in them pairing.
The optical change arising from this coupling is difficult to predict, but it is safe to say that it is very difficult to reliably transfer the optical properties of a fluorescent liquid into a solid.
“The problem of quenching and inter-dye coupling arises when the dyes stand shoulder-to-shoulder inside the solid,” Flood said. “They can’t help ‘touching’ each other. Like young children sitting at story time, they interfere with each other and stop treating individuals.”
Therefore, the team developed a solution to the problem based on the separation of fluorescent molecules. They took a colorless solution of macrocycle molecules called cyanostars and mixed them with a fluorescent dye.
This use of macrocycles – a large class of ring-shaped molecules – is not a new idea, and others have tried it before. But the big difference is that these earlier efforts were used Colorful macrocycles.
As their new solution dried, the team called small-molecule ionic isolation lattices (SMILES) that effectively separated the dye molecules from each other, preventing them from interacting, and their optical properties with high fidelity Prepared to preserve.
“Some people think that colorless macrocycles is ugly, but they allowed the isolation lattice to fully express the bright fluorescence of dyes unencumbered by the colors of the macrocycles,” Flood said.
This material can then be taken in many directions. It can be grown in crystals; It can form a dry powder; Or it can be incorporated directly into the polymer. Researchers found that it works perfectly with many commercially available fluorescent dyes, which, they said in their paper, “characterize these materials as plug and play”.
This means that any currently available fluorescent dye must work on the shelf with the team’s Macro Cycle solution to produce a shiny glowing, solid material that properly preserves the properties of the liquid dye.
But there is still work to be done before coming to that point. The first step was developing content. Now the team has to study it.
“These materials are completely new, so we don’t know exactly which of their innate properties are going to provide better functionality,” Flood said.
“We do not even know the limitations of materials. Therefore, we will develop a basic understanding of how they work, providing a strong set of design rules to create new assets. These materials are in the hands of others. It is important to put in – we want to drive the crowd forward and work with others in this effort. ”
The research has been published in Cell press.