3D exploration of light scattering from live cells in the presence of gold nanomarkers using holographic microscopy

TL;DR

This study demonstrates the use of high-resolution digital holographic microscopy to 3D map light scattering from live cells with gold nanomarkers, enabling clear identification of the nanomarkers amidst cellular structures.

Contribution

It introduces a method combining off-axis heterodyne and phase-shifting holography for 3D localization of gold nanomarkers in live cells, improving detection accuracy.

Findings

Gold nanomarkers produce distinct bright scattering patterns.

The method effectively discriminates nanomarkers from cellular background.

3D localization of nanomarkers is achieved with high precision.

Abstract

In this paper, we explore the 3D structure of light scattering from dark-field illuminated live 3T3 cells in the presence of 40 nm gold nanomarkers. For this purpose, we use a high resolution holographic microscope combining the off-axis heterodyne geometry and the phase-shifting acquisition of the digital holograms. A comparative study of the 3D reconstructions of the scattered fields allows us to locate the gold markers which yield, contrarily to the cell structures, well defined bright scattering patterns that are not angularly titled and clearly located along the optical axis (z). This characterization is an unambiguous signature of the presence of gold biological nanomarkers, and validates the capability of digital holographic microscopy to discriminate them from background signals in live ce