DATE2026.11.13 #Press Releases
One step towards building a “quantum nose”
Scientists successfully create polarized radical pairs in a metal–organic framework, paving the way for quantum sensing
An international research team led by Nobuhiro Yanai from the University of Tokyo and Michael R. Wasielewski from Northwestern University has successfully created polarized radical pairs, molecules with unpaired electrons whose spins align, in metal–organic frameworks (MOFs), a porous material consisting of metal ions linked by organic molecules. Because of the quantum properties of polarized radical pairs, this achievement could provide the foundation for future quantum chemical sensing technologies and improve the sensitivity of existing methods such as magnetic resonance imaging (MRI). The findings were published in the journal Nature Communications.
The formation of spin-polarized radical pairs in a metal–organic framework
At its core, sensing is about detecting changes to specific triggers. Take smelling, for example. Nerve cells specialized for certain chemicals activate when those chemicals are present in the air you breathe in. The activated nerve cells then send a signal to the brain, which translates the signal into “fruity” or “floral.” As scientific understanding deepens, it both requires and enables higher sensitivity, resolution, and variety of sensing, in theory down to the quantum level.
“We are interested in making a quantum nose, so to speak,” says Yanai, the principal investigator. “Although quantum sensing has been a very hot topic in the past decades, leveraging it for chemical sensing has been lagging. Our goal is to make chemical quantum sensing a reality.”
The ingredients for such a sensing technology are fairly well-known. Metal–organic frameworks are highly porous, making them great as containers. Radical pairs have quantum properties that make them suitable as potential sensors.
“Thus far, research into radical pairs has been limited to isolated molecules in solid state,” Wasielewski explains. “So, we set out to develop a method to make an ordered array of radical pairs in a crystalline solid.”
First, the researchers designed and synthesized molecules that could transfer electrons when excited by light. Then, they evaluated each variation using ultrafast spectroscopy, electron paramagnetic resonance spectroscopy, and quantum chemical theory calculations. Such a complex project required the expertise of several teams, transcending borders.
“Thanks to this collaboration,” Yanai says, “we successfully created a pair of radicals and demonstrated the response of their spin properties to some chemical substances. As the next step, we hope to explore a variety of spin systems in metal–organic frameworks and their response to chemical stimuli.”
For more details, please read the article:
Tomoyuki Hamachi, Yuheng Huang, Hannah J. Eckvahl, Angelo Carella, Kathryn R. Peinkofer, Ryan M. Young, Matthew D. Krzyaniak, Takuma Ito, Yuki Kurashige, Reiya Yabuki, Michael R. Wasielewski, and Nobuhiro Yanai. 2026. Sublevel-Selective Electron Spin Hyperpolarization of Triplet Radical Pairs in Metal–Organic Frameworks. Nature Communications. DOI: 10.1038/s41467-026-79262-6