Nanoscale Dynamic Readout of a Chemical Redox Process Using Radicals Coupled with Nitrogen-Vacancy Centers in Nanodiamonds

Jan Barton; Michal Gulka; Jan Tarabek; Yuliya Mindarava; Zhenyu Wang; Jiri Schimer; Helena Raabova; Jan Bednar; Martin B. Plenio; Fedor Jelezko; Milos Nesladek; Petr Cigler

doi:10.1021/acsnano.0c04010

arXiv · 2010.11257

Nanoscale Dynamic Readout of a Chemical Redox Process Using Radicals Coupled with Nitrogen-Vacancy Centers in Nanodiamonds

Jan Barton·Michal Gulka·Jan Tarabek·Yuliya Mindarava·Zhenyu Wang·Jiri Schimer·Helena Raabova·Jan Bednar·Martin B. Plenio·Fedor Jelezko·Milos Nesladek·Petr Cigler

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Abstract

Biocompatible nanoscale probes for sensitive detection of paramagnetic species and molecules associated with their (bio)chemical transformations would provide a desirable tool for a better understanding of cellular redox processes. Here, we describe an analytical tool based on quantum sensing techniques. We magnetically coupled negatively charged nitrogen-vacancy (NV) centers in nanodiamonds (NDs) with nitroxide radicals present in a bioinert polymer coating of the NDs. We demonstrated that the T1 spin relaxation time of NV centers is very sensitive to the number of nitroxide radicals, with a resolution down to ~10 spins per ND (detection of approximately $ 10^-23 $ mol in a localized volume). The detection is based on T1 shortening upon the radical attachment and we propose a theoretical model describing this phenomenon. We further show this colloidally stable, water-soluble system can be used dynamically for spatiotemporal readout of a redox chemical process (oxidation of ascorbic acid) occurring near the ND surface in an aqueous environment under ambient conditions.

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Jan Barton, Michal Gulka, Jan Tarabek, Yuliya Mindarava, Zhenyu Wang, Jiri Schimer, Helena Raabova, Jan Bednar, Martin B. Plenio, Fedor Jelezko, Milos Nesladek, Petr Cigler. 2020-10-21. Nanoscale Dynamic Readout of a Chemical Redox Process Using Radicals Coupled with Nitrogen-Vacancy Centers in Nanodiamonds. https://doi.org/10.1021/acsnano.0c04010

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