High-Sensitivity, High-Resolution Detection of Reactive Oxygen-Species Concentration Using NV Centers

TL;DR

This paper presents a novel NV center-based method for high-resolution, in-situ detection of reactive oxygen species, specifically hydroxyl radicals, with high sensitivity and spatial precision in biological and chemical contexts.

Contribution

It introduces a new fluorescence-based approach using NV centers to quantify ROS with high spatial resolution and sensitivity without spin labels.

Findings

Sensitivity of $11 \\pm 4$ nM/\\sqrt Hz achieved

Localized detection volume of approximately 10 picoliters

In-situ measurement without spin labels

Abstract

Nitrogen-vacancy (NV) color centers in diamond have been demonstrated as useful magnetic sensors, in particular for measuring spin fluctuations, achieving high sensitivity and spatial resolution. These abilities can be used to explore various biological and chemical processes, catalyzed by Reactive Oxygen Species (ROS). Here we demonstrate a novel approach to measure and quantify Hydroxyl radicals with high spatial resolution, using the fluorescence difference between NV charged states. According to the results, the achieved NV sensitivity is $11 \pm 4 \frac{nM}{\sqrt Hz}$, realized in-situ without spin labels and localized to a volume of $\sim 10$ picoliter.