Conducting MR exams with a refrigerator magnet? Just add diamond particles

May 30, 2018
by John W. Mitchell, Senior Correspondent
While it’s all a bit technical, the end result of a study by researchers at the University of California Berkley College of Chemistry (USBCC) suggests that the cost of multimillion-dollar MR machines and nuclear magnetic resonance (NMR) spectroscopy devices could be substantially reduced.

The study, published in Science Advances, makes the case that the same defects in diamonds that account for the color and beauty, when ground into dust, offer a new medium that hints at great promise for enhancing MR signals without huge, expensive magnets.

The breakthrough in the study came when the team figured out how to use a small magnet about the size of that found on a refrigerator, combined with a small laser diode and the electronics used in a WiFi router, to get the needed performance.

“It was surprising that the diamond particles could so easily be hyperpolarized,” Ashok Ajoy, a postdoctoral associate at USBCC and lead author told HCB News. “This was perceived to be very difficult to achieve because different orientations of the particles in a powder behave differently.”

The upshot of this method is that the diamond medium could also offer better images. Diamond particles have defect centers that can be optically hyperpolarized, or have their spins aligned. In theory, the special high-surface areas of nanodiamond particles, when transferred to external liquids, might increase their NMR signature “by orders of magnitude.”

“NMR and MRI are versatile and widely used techniques but suffer from low signal strengths,” Ajoy said. “Our vision is to be able to shine light on materials and have their NMR signal enhanced multifold.”

The proof of principle study concluded that: “Our work paves the way toward the use of hyperpolarized diamond particles as imaging contrast agents for biosensing and, ultimately, for hyperpolarization of nuclear spins in arbitrary liquids brought in contrast with their surface.”

Translated, Ajoy explained that if the hyperpolarization-to-liquids findings in contact with particles (MR scans lock onto cellular water molecules) could be transferred, the resulting images could reinvent MR angiography. This possibility lies in the fact that the huge magnets currently used in MRs would not be needed to achieve even modest increases in signal sensitivity for better disease diagnostics.