Bioparticle separation in non-Newtonian fluid using pulsed flow in micro-channels

Micro total analysis system (μTAS) devices frequently need to deal with bio-particle suspensions in solution and separation of certain bio-particles is often desirable. Separation of plasma from the whole blood has become increasingly popular in clinical diagnostics. Using the coupled volume of fluid (VOF) and the discrete phase (DP) governing equations for multiphase flow, the effect of Newtonian viscosity of water and the non-Newtonian shear-thinning viscosity of blood on particle separation under pulsed pressure condition is determined. It is observed that the red blood cells (RBC) accumulate at the front of the blood column while the opposite is observed in water. For the selected parameters, 20% of the plasma observed is to be separated from the whole blood, while in contrast, for a 98% diluted blood, 45% of the plasma can be separated. The present calculations can be adopted to design the flow parameters necessary for the instantaneous separation of plasma from the whole and the diluted blood for μTAS; thus reducing the number of experimental studies.