title: Hydrodynamic lift of vesicles and red blood cells in flow--from Fåhræus & Lindqvist to microfluidic cell sorting.
abstract: Hydrodynamic lift forces acting on cells and particles in fluid flow receive ongoing attention from medicine, mathematics, physics and engineering. The early findings of Fåhræus & Lindqvist on the viscosity change of blood with the diameter of capillaries motivated extensive studies both experimentally and theoretically to illuminate the underlying physics. We review this historical development that led to the discovery of the inertial and non-inertial lift forces and elucidate the origins of these forces that are still not entirely clear. Exploiting microfluidic techniques induced a tremendous amount of new insights especially into the more complex interactions between the flow field and deformable objects like vesicles or red blood cells. We trace the way from the investigation of single cell dynamics to the recent developments of microfluidic techniques for particle and cell sorting using hydrodynamic forces. Such continuous and label-free on-chip cell sorting devices promise to revolutionize medical analyses for personalized point-of-care diagnosis. We present the state-of-the-art of different hydrodynamic lift-based techniques and discuss their advantages and limitations.
authors.affiliation: EP1, Soft Matter and Biological Physics Group, University of Augsburg, 86159 Augsburg, Germany; Nanosystems Initiative Munich (NIM), Schellingstraße 4, 80799 München, Germany.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Geislinger
authors.affiliation: EP1, Soft Matter and Biological Physics Group, University of Augsburg, 86159 Augsburg, Germany; Nanosystems Initiative Munich (NIM), Schellingstraße 4, 80799 München, Germany; Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom. Electronic address: thomas.franke@glasgow.ac.uk.
authors.forename: Thomas
authors.initials: T
authors.lastname: Franke
mesh_terms: D000465:Algorithms; D000818:Animals; D055592:Biophysical Phenomena; D001703:Biophysics / Q000295:instrumentation / Q000379:methods* / Q000639:trends; D048430:Cell Shape; D004867:Equipment Design; D004912:Erythrocytes / Q000737:chemistry* / Q000378:metabolism; D005434:Flow Cytometry / Q000295:instrumentation; D006801:Humans; D057446:Hydrodynamics; D008081:Liposomes; D008567:Membranes, Artificial; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation; D008954:Models, Biological; D010316:Particle Size
chemical_list: D008081:Liposomes; D008567:Membranes, Artificial
keywords: Cell sorting and separation; Hydrodynamic lift; Lab on a chip; Microfluidics; Red blood cells; Vesicles