Artificial Intelligence-Powered Automated Holotomographic Microscopy Enables Label-Free Quantitative Biology

Abstract

Abstract:Holotomographic microscopy (HTM) measures the refractive index (RI) tomograms of living cells and tissues in three dimensions. The ability to observe biological processes at high spatial and temporal resolution opens uncharted territories for cell biologists, however, current HTM devices have a limited throughput. We show here the first automated multi-well plate-compatible HTM device, the CX-A. Thanks to state-of-the-art environment control and a new type of autofocus, the CX-A can record multiple conditions in parallel over large fields of view, while its software EVE supports automated single-cell segmentation and quantification. This opens the door to new applications for HTM, from drug screening to systems biology.

Holotomography and atomic force microscopy: a powerful combination to enhance cancer, microbiology and nanotoxicology research

“…Recently, HTM has emerged as a powerful label-free three-dimensional (3D) technique for imaging cell components without requiring cell staining and label-free nanoparticles (NPs) inside cells [ 16 ]. Modern HT microscopes offer advantages like no label requirements, low photo-toxicity, quick analysis, acquisition of quantitative data such as refractive index, dry mass, and protein content [ 17 ], which in most samples, the protein concentration is linearly proportional with RI values [ 18 , 19 ]. HTM analysis permits the distinction of organelles without the necessity of fluorescent markers.…”

“…Nowadays, HTM microscopes are commercially available. HTM microscopes differ in design, although modern equipment uses low energy wavelength for measurements, reducing its phototoxicity [ 17 , 18 ]. Figure 3 a illustrates a basic structure of an HTM microscope.…”

“…They report changes in cell volume, dry mass, and surface area of infected cells [ 32 ]. Late HTM equipment integrates Artificial Intelligence to support automated single-cell segmentation and quantification [ 18 ].…”

Holotomography and Atomic Force Microscopy: A Powerful Combination to Enhance Cancer, Microbiology and Nanotoxicology Research

“…Nowadays, HT microscopes are commercially available. HT microscopes differ in design, although modern equipment uses low energy wavelength for measurements, reducing its phototoxicity [9,10]. Figure 3a illustrates a basic structure of an HT microscope.…”

“…Atomic force microscopy can be an accompanying technique to study cell morphology and mechanical properties [10]. Recent AFM microscopes have had significant modifications and advancements for their use in biological research [11].…”