title: Transportation, dispersion and ordering of dense colloidal assemblies by magnetic interfacial rotaphoresis.
abstract: Colloidal systems exhibit intriguing assembly phenomena with impact in a wide variety of technological fields. The use of magnetically responsive colloids allows one to exploit interactions with an anisotropic dipolar nature. Here, we reveal magnetic interfacial rotaphoresis - a magnetically-induced rotational excitation that imposes a translational motion on colloids by a strong interaction with a solid-liquid interface - as a means to transport, disperse, and order dense colloidal assemblies. By balancing magnetic dipolar and hydrodynamic interactions at a symmetry-breaking interface, rotaphoresis effectuates a translational dispersive motion of the colloids and surprisingly transforms large and dense multilayer assemblies into single-particle layers with quasi-hexagonal ordering within seconds and with velocities of mm s(-1). We demonstrate the application of interfacial rotaphoresis to enhance molecular target capture, showing an increase of the molecular capture rate by more than an order of magnitude.
authors.affiliation: Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: van Reenen
authors.forename: A M
authors.initials: AM
authors.lastname: de Jong
authors.forename: M W J
authors.initials: MW
authors.lastname: Prins
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000276:immunology; D003102:Colloids / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D007074:Immunoglobulin G / Q000737:chemistry / Q000276:immunology; D008280:Magnetics; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation; D008856:Microscopy, Fluorescence
chemical_list: D001426:Bacterial Proteins; D003102:Colloids; D005456:Fluorescent Dyes; C034284:IgG Fc-binding protein, Streptococcus; D007074:Immunoglobulin G