The influence of electrokinetic charge and deformability of the red blood cell on the flow properties of its suspensions 1

The effects of changes in association, flexibility and electrokinetic charge of red blood cells on the flow properties of their suspensions were studied using the screen filtration pressure (SFP) method and cone-plate viscometry. The SFP is dependent mainly on aggregation and adhesiveness of the cells; the volume concentration of the cells and viscosity of the plasma playing less important roles. The viscosity at moderate rates of shear depends on the volume concentration of the cells whilst aggregation and adhesiveness play a minor role.

Decreasing the electrokinetic charge of the red cells by treatment with neuraminidase or uranyl nitrate, or prehardening the cells with acetaldehyde produce no significant change in the cone-plate measurements for rates of shear >11.5 sec⁻¹ at volume concentrations <45 per cent. At volume concentrations >50 per cent the “viscosity” of the suspensions of prehardened cells increases much more rapidly with volume concentration than for normal red cell suspensions.