Hydrodynamic Red Blood Cells Deformation by Quantitative Phase Microscopy and Zernike Polynomials

Abstract

Red Blood Cells (RBCs) deformability is an important parameter for evaluating their health status. Its quantification is performed through the measurement of erythrocyte's shape stiffness when subjected to external stimuli. Here, we exploit the hydrodynamic deformation of RBCs in microfluidic channels to quantify the shape variations through quantitative phase imaging by digital holography. In particular, two main processing steps have been employed, i.e., the morphological analysis based on quantitative phase variations and a new way to monitor the entire cell's deformation, based on modeling RBCs as a micro-lenses array. In fact, taking advantage of the RBC lens behavior, it is possible to correlate optical aberrations generated by the mechanical stimulus to the entire membrane deformation itself, through a numerical analysis based on Zernike polynomials. We provide a proof of principle of how to use Zernike analysis for characterizing RBCs' deformability under hydrodynamic stress. We demonstrate that new optical parameters of RBCs can be measured and analyzed, thus opening the route to the exploitation of the bio-lens model as a biomechanical marker of RBCs.

Biophotonic probes for bio-detection and imaging

“…(Fig. 11b ) 174 . Cellular deformations were induced mechanically by accurate manipulation of shear stress in microfluidic streams (Fig.…”

“…Copyright 2018, American Chemical Society. b RBC lens behavior as a biomechanical marker to monitor the deformations of the RBCs 174 . Copyright 2019, Frontiers.…”

Real-Time Reconstruction of the Complex Field of Phase Objects Based on Off-Axis Interferometry

“…Consequently, the dynamic imaging of the phase only caused by the sample could be achieved. To verify the feasibility of the imaging system, we have demonstrated the experiments on polystyrene microspheres and red blood cells [20][21][22][23].…”

Wide-Field Pixel Super-Resolution Colour Lensfree Microscope for Digital Pathology

“…Most of the colour lensfree holography focuses on the phase retrieval of the holographic image, eliminating the interference of the twin image and colour artifacts on the reconstructed image. Currently, the colour imaging method focuses on the three wavelengths of red, green and blue (RGB) for separate illumination ( 28 , 29 ), combined with multi-height phase retrieval or using colour image sensors to receive holograms of three wavelengths of RGB to create a colour image of the object. However, it does not consider the resolution enhancement processing of the colour image, making it unsuitable for the high-resolution imaging of a stained pathological slide.…”