Abstract

Design of Deterministic Lateral Displacement Microfluidic Separators for Bioclinical Applications: Where Do We Stand?

stefano cerbelli, Associate Professor, Sapienza University of Rome

Deterministic Lateral Displacement (DLD) has emerged fifteen years ago as an efficient alternative to traditional techniques for the size-based sorting of mesoscopic objects suspended in a flowing continuum. In DLD-based separators, the suspension is forced by a pressure-driven flow through a spatially periodic array of micrometric obstacles and migrate along different directions according to their size. Biological/clinical applications of this technique range from exosomes to red blood and circulating cancer cells. Despite its experimentally demonstrated ability to achieve unprecedented separation resolution, DLD-based separation devices have yet to overcome the gap between prototype and commercial stage. In this contribution, an overview of recent results stemming from a theoretical/computational approach developed by this author and co-workers is presented. This approach, which explicitly accounts for the presence of Brownian thermal fluctuations of the suspended particles, yields results that are qualitatively consistent with experiments. Specifically, the modelling approach accounts for the dependence of the particle migration angle on their diffusivity, as well as for the yet unexplained enhanced particle dispersion observed in experiments conducted at different flowrates. The practical implications of the results for the optimized design of DLD devices for tailored applications involving separation of populations of suspended cells is discussed in detail.