Filter-less submicron hydrodynamic size sorting

Abstract

International audienceWe propose a simple microfluidic device able to separate submicron particles (critical size ~0.1 µm) from a complex sample with no filter (minimum channel dimension being 5 µm), by hydrodynamic filtration. A model taking into account the actual velocity profile and hydrodynamic resistances enables predicting the chip sorting properties for any geometry. Two design families are studied to obtain (i) small sizes within minutes (low-aspect ratio, two-level chip) and (ii) micron-sized sorting with µL flowrate (3D architecture based on lamination). We obtain quantitative agreement of sorting performances both with experiments and with numerical solving, and determine the limits of the approach. We therefore demonstrate a passive, filter-less sub-micron size sorting with simple, robust, easy to fabricate design