Diamond may be the key to the future of MRI / magnetic resonance imaging technology

    Alex Pines research team recorded the first piece at room temperature under an arbitrary magnetic field and the crystal orientation,DIAMONDCarbon-13 NMR in situ hyperpolarized nuclei.

    Alexander Pines is a senior professor at Berkeley Lab's Materials Sciences Division and UC Berkeley Glenn T. Seaborg Professor of Chemistry Institute of seats, led a study in which, the researchers recorded the first piece at room temperature under an arbitrary magnetic field and the crystal orientation,DIAMONDCarbon-13 NMR in situ hyperpolarized nuclei. Carbon-13 spin signal display hyperpolarized NMR / MRI signal sensitivity obtained with respect to the conventional NMR / MRI magnet at room temperature is usually a plurality of possible signal exceeds the magnitude of sensitivity enhancement. In addition, this hyperpolarization is achieved using microwave, rather than relying on the magnetic field to be precise hyperpolarization transfer.

    Pines was published in "Nature Communications" on an article about this study was the corresponding author. The paper is entitled "King Shi Zhongguang room temperature in situ pumping nitrogen vacancy center of nuclear spin hyperpolarization." A member of the research team JonathanKing Pines is the first author of this paper.

    The authors report, observed six percent of body nuclear spin polarization, which is a large thermal equilibrium than 170,000 times around nuclearMRISignal enhancement. Spin hyperpolarization signal can be detected by standard in situ NMR probe, the sample does not need to move back and forth, or a precise crystal orientation. The author believes this new technology should enable hyperpolarization sensitivity at room temperature for solids and liquids NMR studies on the magnitude enhanced.

    "Our findings represent a result of Weizmann Institute of Science Lucio Frydman and his colleagues obtained their groundbreaking experiment in a considerable enhancement of the NMR signal, but it is in diamond induced dynamic hyperpolarized nuclei through the microwave, not requires precise control of the magnetic field and the crystal orientation, "Pines said:" The room hyperpolarized diamond open NMR / MRI polarization from an inert, non-toxic, easy to separate the source is transferred to the possibility of any sample, which is contemporary NMR / MRI technology a long-sought goal. "

Both specific and non-destructive chemical characteristics make NMR / MRI technology in a wide range of areas, including chemistry, materials, biology and medicine has become an indispensable technology. However, its sensitivity remains a constant challenge. NMR / MRI signal is based on the intrinsic quantum properties of electrons and nuclei is called a "spin" of. Electrons and nuclei can be like a small bar magnet rotation is assigned as an "up" or "down" direction state. NMR / MRI signals in one direction depends on the polarization of the nuclear spins of the majority - that is, the higher the degree of polarization, the stronger the signal. Pines and his research team after decades of effort, has developed a number of methods to hyperpolarized nuclei spin. In the past two years, they have been focused on diamond crystals and called nitrogen-vacancy (NV) center impurities in a nitrogen vacancy center optical and spin freedom are coupled together.

"When pure diamond crystal lattice in two adjacent carbon atoms are removed from the crystal lattice, leaving two holes, one of which is filled with a nitrogen atom, and the other holding vacant when to get a nitrogen vacancy (NV) center, "Pines explained. This makes it appear unbound electrons between nitrogen atoms and vacancies, produce a unique and clear electron spin polarization states. "

In previous studies, Pines and his team found that low intensity magnetic field can be used to transmit NV center electron spin polarization to nearby carbon-13 nucleus, resulting in hyperpolarized nuclei. The spin transfer is called dynamic nuclear polarization process in the past had been used to enhance the NMR signal, but always performed at high intensity magnetic fields and low temperatures. Pines and his team next to diamond by placing a permanent magnet eliminates these requirements.

"In our new study, we use the microwave instead of a magnetic field to match the energy between electrons and carbon-13 nuclei, thus eliminating some of the difficulties of the restrictions on the magnetic field strength and alignment, making our technology easier to use, "King said:" In addition, in our previous study, we infer the existence of indirect nuclear polarization by an optical measurement, because we can not test the sample as a whole or only very close to the polarization of nuclear NV center is polarized by completely eliminated. Correctmagnetic fieldNeeds, we are now able to directly measure the bulk sample by NMR.

In "Nature Communications" in the article, Pines, King and other co-authors say, it can be effectively integrated into existing manufacturing techniques and the creation of hyperpolarized diamond diamond high surface area of ​​the device should be able to provide a common polarization transfer platform.

"We want to use the existing polarization transfer techniques - such as solid and liquid cross-polarization cross-relaxation, or NV centers directly dynamic nuclear polarization nuclear periphery - to be highly liquid and solid nuclear magnetic enhancement resonance, "King said, it should be noted that this has been transferred to the research team used laser Pines polarized Xe-129 argued before the polarization of solid surfaces and liquid transfer. "We are more powerful technology based on optical polarization hyperpolarization NV centers and effective, it should be applied to any target molecule, including the need to maintain at near ambient conditions of biological systems."