Spin-based magnetic detection of optically trapped single cell in microfluidic channel

TL;DR

This paper introduces a magnetic detection method using nitrogen-vacancy centers integrated with optical tweezers to precisely trap and analyze single cells in microfluidic channels, overcoming fluorescence detection limitations.

Contribution

The study develops a novel magnetic detection strategy combining quantum magnetometry with optical tweezers for single-cell analysis in microfluidic environments.

Findings

Detected a magnetic signal of 89 μT from a single labeled cell.

Noise floor of 3.9 μT in unlabeled cells.

Platform enables high-precision single-cell magnetic analysis.

Abstract

Combining optical tweezers with fluorescence microscopy is a powerful tool for single-cell analysis, playing a pivotal role in disease diagnosis, cell sorting, and the investigation of cellular dynamics. However, fluorescence detection faces challenges such as blinking, photobleaching and autofluorescence in biotissues. To address these limitations, we developed a magnetic detection strategy by integrating quantum magnetometry using nitrogen-vacancy centers into optical tweezers, demonstrating precise trapping and manipulation of individual cells in microfluidic environment. We detected a magnetic signal of 89 {\mu}T from a single cell labeled with magnetic nanoparticles, compared to a noise floor of 3.9 {\mu}T observed in unlabeled cells. This platform provides a promising approach for high-precision single-cell analysis and holds significant potential for probing cellular activities within biological microenvironments.