Experimental and theoretical study of light scattering by individual mature red blood cells by use of scanning flow cytometry and a discrete dipole approximation

Abstract

Elastic light scattering by mature red blood cells (RBCs) was theoretically and experimentally analyzed with the discrete dipole approximation (DDA) and the scanning flow cytometry (SFC), respectively. SFC permits measurement of angular dependence of light-scattering intensity (indicatrix) of single particles. A mature RBC is modeled as a biconcave disk in DDA simulations of light scattering. We have studied the effect of RBC orientation related to the direction of the incident light upon the indicatrix. Numerical calculations of indicatrices for several aspect ratios and volumes of RBC have been carried out. Comparison of the simulated indicatrices and indicatrices measured by SFC showed good agreement, validating the biconcave disk model for a mature RBC. We simulated the light-scattering output signals from the SFC with the DDA for RBCs modeled as a disk-sphere and as an oblate spheroid. The biconcave disk, the disk-sphere, and the oblate spheroid models have been compared for two orientations, i.e. face-on and rim-on incidence. Only the oblate spheroid model for rim-on incidence gives results similar to the rigorous biconcave disk model.

Systematic comparison of the discrete dipole approximation and the finite difference time domain method for large dielectric scatterers

“…High-absorbing materials, which also are of great interest in many applications, are saved for another study. We have extended experience in using both methods for simulating light scattering by biological cells [8][9][10][11][12]. To verify our conclusions made for spheres we also perform simulations for a few realistically shaped biological cells.…”

Mature red blood cells: from optical model to inverse light-scattering problem

“…In this study we modernize the angle-resolved light-scattering approach based on the scanning flow cytometer (SFC) [5,9,10] for complete and rapid characterization of RBCs from light-scattering profiles (LSP). The new method does not require chemical spherization of RBCs and utilizes the solution of the inverse light-scattering (ILS) problem, using the optical model of a mature RBC.…”

Theoretical models for near forward light scattering by aPlasmodium falciparuminfected red blood cell

“…The absorption and scattering cross-sections obtained from Mie theory were used by Steinke and Shephered [24] to describe light transport in the blood. More recently, rigorous simulations of light scattering by realistic RBCs have become possible employing a variety of numerical methods [27][28][29][30][31][32][33]. The results generally conclude that the approximation of RBC shape by a volumeequivalent sphere is not sufficiently accurate.…”