Nuclear Magnetic Resonance Detection and Spectroscopy of Single Proteins Using Quantum Logic

February 8, 2016

Fig. 1(A)*.    [Reprinted with permission from AAAS]

Nuclear magnetic resonance spectroscopy is a powerful tool for the structural analysis of organic compounds and biomolecules, which, unril now, typically required macroscopic sample quantities. In a new paper in Science, however, a team of physicists led by Mikhail Lukin and Hongkun Park reported on utilizing a sensor, consisting of two quantum bits corresponding to an electronic spin and an ancillary nuclear spin, to demonstrate room temperature magnetic resonance detection and spectroscopy of multiple nuclear species within individual ubiquitin proteins attached to the diamond surface. Using quantum logic to improve readout fidelity and a surface treatment technique to extend the spin coherence time of shallow NV centers, the physicists demonstrated magnetic field sensitivity sufficient to detect individual proton spins within one second of integration. This gain in sensitivity enables high-confidence detection of individual proteins and allows scientists to observe spectral features that reveal information about their chemical composition.

*See I. Lovchinsky, A.O. Sushkov, E. Urbach, N.P. de Leon, S. Choi, K. De Greve, R. Evans, R. Gertner, E. Bersin, C. Müller, L. McGuinness, F. Jelezko, R. L. Walsworth, H. Park, M.D. Lukin, "Nuclear magnetic resonance detection and spectroscopy of single proteins using quantum logic," Science 04 Feb 2016 | DOI: 10.1126/science.aad8022.