Assessing erythrocyte filterability with 3 μ m pore size polycarbonate membranes at constant cell flux

Abstract

Erythrocyte deformability for suspensions of washed normal cells was tested by measuring the initial pressure drop during constant volumetric flow through 3-μm pore size Nuclepore membranes. Filtrations of erythrocytes with the smaller pore size membranes were less sensitive to contaminating leukocytes and independent of leukocyte concentration when less than 100 cells/mm³ at red cell number densities of 3.85 × 10⁵ cells/mm³. Constant wall shear rate experiments at different erythrocyte fluxes show that the increase of initial pressure drop is nearly linear with the increase of erythrocyte flux over an order of magnitude range in flux. Constant erythrocyte flux experiments at different wall shear rates suggest viscous shear thinning of erythrocyte suspensions.