Miniaturized optimal incident light angle‐fitted dark field system for contrast‐enhanced real‐time monitoring of 2D/3D‐projected cell motions

Abstract

In the eld of biology, dark eld microscopy provides superior insight into cells and subcellular structures.However, most dark eld microscopes are equipped with a dark eld lter and a light source on a 2Dbased specimen, so only a at sample can be observed in a limited space. We propose a compact cell monitoring system with built-in dark eld lter with an optimized incident angle of the light source to provide real-time cell imaging and spatial cell monitoring. 2D/3D projected dark eld images are optimized for 2D/3D samples as they rely on dark eld lters, and incident light. 2D projection imaging was implemented using a modular condenser lens to acquire high-contrast images. This enabled the long-term monitoring of cells, and the real-time monitoring of cell division and death. This system was able to image, by 2D projection, cells on the surface thinly coated with multi-walled carbon nanotubes, as well as living cells that migrated along the surface of glass beads and hydrogel droplets with a diameter of about 160 μm. The Optimal incident light angle-tted dark eld system combines high-contrast imaging sensitivity and high spatial resolution to even image cells on three-dimensional surfaces.