Cecilia Rorai (Nordita)
Living cells are usually immersed in fluids they interact with. The nature of the interaction is complex and involves biochemical and biophysical mechanisms. Even when the problem is simplified to account for the hydrodynamical aspects only, it turns out that cells cannot be regarded as "passive". The fluid flow and the motion of the cell are mutually and nonlinearly coupled due to the deformability of the cell membrane. This leads to a multiplicity of hardly predictable dynamical behaviors exploited by nature in biological systems and by humans in microfluidic devices for medical diagnostic. The problem is strongly dependent on the flow geometry and the deformability of the membrane. We have numerically studied flow geometries that allow for cell alignment and sorting. We present and discuss some preliminary results and we propose a microfluidic device able to sort cells, modeled as elastic capsules, by deformability.