A research team co-led by the University of Iowa has developed a new approach that uses ultra-tiny diamond sensors to detect temperature changes in cells, which could lead to better diagnosis of diseases such as cancer.
The sensors are based on physics at the quantum level, the unseen world where atoms and even smaller constituents act in strange and surprising ways. This frontier is intriguing for a wide range of potential applications, including computing, medical imaging, navigation, and more advanced sensors.
Scientists have explored using nanodiamonds as intracellular thermometers, leveraging shifts in their energy levels to measure temperature within cells. It was assumed that these shifts were the result of the diamond responding only to the cell’s temperature.
But the research team, including scientists at the University of Chicago, discovered that there is more to the story: The diamond’s surface also contributed to the shifts.
Why It Matters
Diamond-based quantum sensors, ultra-tiny devices that use special defects inside diamonds for detection and measurements, could help scientists detect subtle changes in cells associated with diseases such as cancer at earlier stages, study how other diseases develop, and better understand how healthy cells function. The findings in this study could establish an important foundation for developing more precise tools for biomedical research and, potentially, future diagnostic technologies.
The findings could open opportunities to use diamond-based quantum sensors to make more accurate temperature readings of cells, and thus to better understand changes within a cell that could pinpoint the beginnings or early-stage development of disease.
Denis Candido, assistant professor in the UI Department of Physics and Astronomy and a co-corresponding author on the study, provided the theoretical underpinnings for the experiments conducted at the University of Chicago.
“This research lays out an important framework for distinguishing between changes in temperature and electric field signal from these sensors, thereby improving the accuracy of temperature sensing in cells with nanodiamonds,” Candido says.
The research team also solved a puzzle for the scientific community. Previously, researchers had interpreted these energy-level shifts as evidence that the temperature inside cells was changing by 2 degrees to 18 degrees Fahrenheit, a range that is physically unrealistic.
“Unraveling the wide energy-level shifts was very
important for advancing the capability of these sensors,” Candido says. “Not only that, but we established that our approach is necessary to obtain accurate temperature readings with nanodiamonds.”
The study, “Probing cellular activity via charge-sensitive quantum nanoprobes," was published online in the journal Advanced Materials.
Co-corresponding authors are Aaron Esser-Kahn and Peter Maurer, from the University of Chicago. Michael Flatté, professor in the Department of Physics and Astronomy at Iowa, is a co-author.
Other contributing authors, from the University of Chicago, are Uri Zvi, Shivam Mundhra, David Ovetsky, Qing Chen, Aidan Jones, Stella Wang, Maria Román-Vazquez, Marie Kim, Udoka Ibeh, Michele Ferro, Kunle Odunsi, Marina Garassino, and Melody Swartz.
The National Science Foundation, the National Institutes of Health, and the U.S. Department of Energy funded the research.