Flow cytometry is a technique widely used in biology and medicine for high-throughput acquisition of various parameters from cells in flow. Beside the established detection of scattering and fluorescence signals with single point detectors, several microscopy techniques have been combined with microfluidic systems to achieve imaging flow cytometry. Among these methods, Quantitative Phase Imaging (QPI) based on off-axis Digital Holographic Microscopy (DHM) is a label-free technique for time-resolved quantitative image analysis of almost transparent biological samples, enabling biophysical cellular features such as refractive index, volume and dry mass. When combined with Bright-Field (BF) microscopy, multimodal DHM systems provide complementary high-resolution intensity images with minimized coherence induced noise, allowing an improved identification of the regions of interest in cell cultures that are suitable for QPI analysis, the identification of small absorbing intracellular structures, and collocation of absorbance and phase changes induced by the different organelles within the cells. Recently, we have implemented a simple and robust single-capture BF and DHM imaging technique within a commercial bright-field microscope named Single Capture Bright Field and Spatially Multiplexed Interferometric Microscopy (SC-BF-SMIM). Here, SC-BF-SMIM technique is combined with a common microfluidic layout which allows the analysis of flow living cells. The platform is characterized for evaluation of living cells in flow, and its capability for imaging flow cytometry is demonstrated.
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