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In situ electron paramagnetic resonance spectroscopy using single nanodiamond sensors.

ABSTRACT: An ultimate goal of electron paramagnetic resonance (EPR) spectroscopy is to analyze molecular dynamics in place where it occurs, such as in a living cell. The nanodiamond (ND) hosting nitrogen-vacancy (NV) centers will be a promising EPR sensor to achieve this goal. However, ND-based EPR spectroscopy remains elusive, due to the challenge of controlling NV centers without well-defined orientations inside a flexible ND. Here, we show a generalized zero-field EPR technique with spectra robust to the sensor's orientation. The key is applying an amplitude modulation on the control field, which generates a series of equidistant Floquet states with energy splitting being the orientation-independent modulation frequency. We acquire the zero-field EPR spectrum of vanadyl ions in aqueous glycerol solution with embedded single NDs, paving the way towards in vivo EPR.

SUBMITTER: Qin Z

PROVIDER: S-EPMC10560202 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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In situ electron paramagnetic resonance spectroscopy using single nanodiamond sensors.

Qin Zhuoyang Z Wang Zhecheng Z Kong Fei F Su Jia J Huang Zhehua Z Zhao Pengju P Chen Sanyou S Zhang Qi Q Shi Fazhan F Du Jiangfeng J

Nature communications 20231007 1

An ultimate goal of electron paramagnetic resonance (EPR) spectroscopy is to analyze molecular dynamics in place where it occurs, such as in a living cell. The nanodiamond (ND) hosting nitrogen-vacancy (NV) centers will be a promising EPR sensor to achieve this goal. However, ND-based EPR spectroscopy remains elusive, due to the challenge of controlling NV centers without well-defined orientations inside a flexible ND. Here, we show a generalized zero-field EPR technique with spectra robust to t ...[more]

PMID: 37805509

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