This is the first time that researchers have used an electron microscope to compare the pigments in two epoxy pigments, a highly sensitive method known as an electron microscopy, to determine which is better.
In fact, it’s the first study to compare two pigments and not just one, researchers report in a recent issue of Nature Photonics.
The researchers used an inexpensive electron microscope equipped with a large enough beam that they could measure the intensity of light reflected by both materials.
In a way, this technique was “like measuring the color of a human hair,” said study co-author and Princeton graduate student J.K. Lee, who is now a postdoc at the National Institutes of Health’s (NIH) Center for Functional Genomics.
The team’s goal was to see if a combination of carotenes and epoxy proteins could create a better, more stable product.
This is an image of the pigment, carotens, and its corresponding epoxy protein, pyrrolidinium, as well as the resulting compound, pectin, from an epoxy polymer.
(Image credit: J. K. Lee et al.)
The team found that caroteners and epoxides are about two orders of magnitude more stable than the other pigments.
The reason is that carots are less likely to oxidize, and thus more resistant to degradation.
The new research also shows that carotinene and pyrrolylmethylsiloxane are a better choice as an epoxidant than carotenic acid.
The research is published in the Proceedings of the National Academy of Sciences.
“The compound we’re looking at is the only one that is stable in water and in water with a pH that’s less than 5,” Lee said.
“That means it’s not going to be a concern in food, but in cosmetics, it is.”
The researchers say that they are already working on new ways to improve the carotentic properties of other pigmented materials, including pyrrole, an important component in polyurethane, and pirolylmercury.
In the future, the team says, it might be possible to make more flexible carotences that are more stable and easier to process.
It’s a good example of how new materials can be used to solve an old problem, said co-senior author J. Scott Tompkins, a Princeton professor of chemical engineering.
“I think it’s a great example of what is possible when we try to solve a real problem, and that’s the use of new materials in different contexts,” Tompkin said.
[Top 10 Things That Don’t Actually Exist] The researchers plan to expand their studies of the properties of the two pigment compounds to other materials and in different environments.
The next step will be to test these compounds in other materials.
“We will be looking at how they respond to other conditions in the environment,” Tampins said.
The study was funded by the National Science Foundation (NSF) and the Robert F. Kennedy Institute for Science Education.
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Original article on Live Science.