title: Micro-fluidic actuation using magnetic artificial cilia.
abstract: We demonstrate advanced fluid manipulations using magnetic polymeric artificial cilia on the walls of a microfluidic channel. In nature, cilia are little hairs covering the surface of micro-organisms which enable them to manipulate a fluid on the micro-scale. The asymmetric movement of natural cilia is crucial to obtain a net fluid flow. We have developed a ferromagnetic polymer made from iron nanoparticles and polydimethylsiloxane, and describe a process that can structure the material into high aspect ratio lying artificial cilia with a length of 300 microm. These artificial cilia were actuated with a homogeneous rotating magnetic field (micro(0)H < 50 mT) generated with a compact external electromagnet. An asymmetric movement involving torsion could be created when the cilia were provided with a remanent magnetisation perpendicular to the plane of rotation of the magnetic field vector. The artificial cilia could be actuated in fluid up to a frequency of approximately 50 Hz. In an aqueous solution in a microfluidic chamber we were able to generate rotational as well as translational fluid movements with fluid velocities up to approximately 0.5 mm s(-1).
authors.affiliation: Eindhoven University of Technology, P.O. Box 513, 5600, MB, Eindhoven, The Netherlands. f.fahrni@tue.nl
authors.forename: Francis
authors.initials: F
authors.lastname: Fahrni
authors.forename: Menno W J
authors.initials: MW
authors.lastname: Prins
authors.forename: Leo J
authors.initials: LJ
authors.lastname: van Ijzendoorn
mesh_terms: D004129:Dimethylpolysiloxanes / Q000737:chemistry; D055119:Elastic Modulus; D004867:Equipment Design; D005290:Ferric Compounds / Q000737:chemistry*; D008280:Magnetics; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D009038:Motion; D053758:Nanoparticles / Q000737:chemistry
chemical_list: D004129:Dimethylpolysiloxanes; D005290:Ferric Compounds; C001215:ferrite; C013830:baysilon