Label-free image scanning microscopy for kHz super-resolution imaging and single particle tracking

TL;DR

This paper presents a modified label-free image scanning microscopy technique capable of kHz super-resolution imaging and single particle tracking, enabling high-speed, high-resolution observation of nanoparticles and bacteria.

Contribution

The authors develop a fast, label-free ISM with optical super-resolution and kHz imaging, enhancing nanoparticle and bacterial tracking capabilities.

Findings

Achieved 24kHz asynchronous 2D imaging with super-resolution.

Tracked nanoparticles down to 20nm for gold and 50nm for silica.

Imaged freely moving bacteria with improved resolution.

Abstract

We report the modification of a label-free image scanning microscope (ISM) to perform asynchronous 2D imaging at 24kHz while keeping the lateral resolution gain and background rejection of a regular label-free ISM setup. Our method uses a resonant mirror oscillating at 12kHz for one-direction scanning and a chromatic line for instantaneous scanning in the other direction. We adapt optical photon reassignment in this scanning regime to perform fully optical super-resolution imaging. We exploit the kHz imaging capabilities of this confocal imaging system for single nanoparticle tracking down to 20nm for gold and 50nm for silica particles as well as imaging freely moving Lactobacillus with improved resolution.