New technology promises to track single molecules traveling through the body

March 12 (UPI) -- Scientists at Duke University have developed technology that could soon allow researchers to track a single drug molecule as it travels through the human body.

The technology uses a chemical tag that causes the host molecule to light up under magnetic resonance imaging. When the molecule interacts with other molecules inside the body, the MRI tag's fluorescence changes frequency.

The technology could allow researchers to better understand how a drug is metabolized by the body.

"MRI methods are very sensitive to small changes in the chemical structure, so you can actually use these tags to directly image chemical transformations," Thomas Theis, an assistant research professor in Duke's chemistry department, said in a news release.

MRI tags aren't new, but Duke scientists have developed a more precise and versatile way to attach tags to target molecules, using a kind of chemical velcro.

"The tags are like lightbulbs covered in Velcro," said Duke grad student Junu Bae. "We attach the other side of the Velcro to the target molecule, and once they find each other they stick."

The velcro technique makes the tags bioorthogonal, meaning they stick only to the target molecules and ignore all others.

When the tag binds with its molecular target, the chemical reaction produces a unique form of nitrogen gas. Scientists say the gaseous byproduct could prove useful when investigating problems with the pulmonary system.

"One could dream up a lot of potential applications for the nitrogen gas, but one that we have been thinking about is lung imaging," Theis said.

Researchers detailed their new technology in the journal Science Advances.

Scientists are now working to ensure the tags can survive the different chemical environments found in the human body. They're also working to boost the intensity with which the molecular tags light up.