It is not easy to ensure that drugs and supplements are turning in the right direction with – or chiral – structures. Now, penetrating infrared light can probe both the structures of molecular crystals and their twists, research led by the University of Michigan has shown.
Researchers hope that the technique may also help diagnose harmful accumulations of folded molecules in the body, including bladder stones, insulin fibrils and amyloid aggregations such as the plaques seen in Alzheimer’s disease.
In the world of curved molecules, biology often favors either the right- or left-handed versions. Walking along the complement aisle, you may notice that some have an L or a D next to their name. L and D denote the direction in which the molecule turns, clockwise or counterclockwise – only one version the human body usually uses. Molecules with the wrong twist can be nuisance fillers or cause side effects that can be unpleasant or even dangerous. But quality control for twisted molecules is difficult, and monitoring of the chiral structures of drugs and supplements placed in storage is not usually performed.
“The methods commonly used in pharmaceutical companies are very sensitive to impurities, but chirality is expensive to measure,” said Wonjin Choi, a research fellow in chemical engineering at UM and first author of the paper in Nature Photonics.
The new method can quickly detect misfolding and wrong chemical structures in packaged drugs using terahertz radiation, a portion of the infrared part of the spectrum. It was developed by an international team, which included researchers from the Federal University of So Carlos, Brazil; Brazilian Biorenewables National Laboratory; University of Notre Dame; and Michigan State University.
Professor Nicolas Kotov from the Irving Langmuir Distinguished University said, “Biomolecules produce curved, long-range vibrations also known as chiral phonons. These vibrations are very sensitive to the structure of molecules and their nanoscale assemblies, which are a characteristic of chirality.” form the fingerprints of the structure.” and co-corresponding author of Chemical Science and Engineering at U-M.
The team was able to measure these phonons in the spectra of twisted terahertz light that passed through the test material. One of these, L-carnosine, is currently used as a nutritional supplement.
“If the twist of the molecule is wrong, if the twist is not right in the way the molecules are packed together, or if different materials have been mixed, it can all be inferred from the spectra,” Kotov said.
John Kruger, a professor of veterinary medicine at Michigan State University and a co-author of the paper, provided bladder stones from dogs, and the team discovered their chiral signature. The team hopes that the findings could help enable rapid diagnosis for pets, and perhaps later for humans. In addition, he studied insulin as it evolved into nanofibers that render it inactive. If terahertz lighting technology can be adapted to home health care, it could verify the quality of insulin.
The team also explored how light can affect structures, rather than just measuring them. Calculations by André Farias de Moura, professor of chemistry at the Federal University of So Carlos and co-corresponding author, show that many biomolecules strongly twist and vibrate when terahertz light generates chiral phonons.
De Moura said, “We anticipate new roads ahead – for example using terahertz waves with analogous polarization to manipulate large molecular assemblies. This could replace microwaves in many synthesis applications in which molecules are manipulated.” Harmony matters.”
Based on de Moura’s calculations, Kotov and Choi believe that the twisting vibrations of chiral phonons caused by terahertz light may make disease-causing nanofibers more vulnerable to medical intervention. Future work will explore whether that conversation can be used to break them up.
This work was supported by the US Department of Defense, the Office of Naval Research, the Defense Advanced Research Projects Agency and the National Science Foundation; Brazilian funding agencies CAPES and FAPESP; Japanese Society for the Promotion of Science and Yoshida Foundation; and UM.
The material was studied at the Michigan Center for Materials Characterization. Kotov also Joseph B. and Florence V. Sejka is Professor of Engineering and Professor of Chemical Engineering, Materials Science and Engineering, and Macromolecular Science and Engineering.
,#Terahertz #light #produces #twisting #vibrations #biomolecules #proteins #confirming #conformations #structures #safe #effective #Science #Daily #Source # Terahertz light produces twisting vibrations in biomolecules such as proteins, confirming whether their conformations and structures are safe and effective. — Science Daily