Flow study on a transparent two-phase blood model fluid based on alginate microspheres

The reduction of blood damage is still a big challenge in blood-carrying medical devices. In vitro experiments are performed to investigate the damage-causing effects, but due to the opaqueness of blood cells, only near-wall flows can be observed. Thus, several transparent blood models to visualize the rheologic behavior of blood have been proposed and examined. Nevertheless, two-phase blood models with added particles still represent the properties of blood inadequately or are very expensive and complex to produce. In this in vitro study, the viscosity, the flow behavior and the cell deformation of human red blood cells have been compared to a novel, easy-to-produce, two-phase blood model fluid with deformable alginate microspheres. The comparison has been performed in a cone-plate rheometer, a straight and a hyperbolic converging microchannel. The viscosity of the blood model fluid with a particle fraction of 30