title: Selectively manipulable acoustic-powered microswimmers.
abstract: Selective actuation of a single microswimmer from within a diverse group would be a first step toward collaborative guided action by a group of swimmers. Here we describe a new class of microswimmer that accomplishes this goal. Our swimmer design overcomes the commonly-held design paradigm that microswimmers must use non-reciprocal motion to achieve propulsion; instead, the swimmer is propelled by oscillatory motion of an air bubble trapped within the swimmer's polymer body. This oscillatory motion is driven by the application of a low-power acoustic field, which is biocompatible with biological samples and with the ambient liquid. This acoustically-powered microswimmer accomplishes controllable and rapid translational and rotational motion, even in highly viscous liquids (with viscosity 6,000 times higher than that of water). And by using a group of swimmers each with a unique bubble size (and resulting unique resonance frequencies), selective actuation of a single swimmer from among the group can be readily achieved.
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Ahmed
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Mengqian
authors.initials: M
authors.lastname: Lu
authors.affiliation: Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Amir
authors.initials: A
authors.lastname: Nourhani
authors.affiliation: Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Lammert
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Zak
authors.initials: Z
authors.lastname: Stratton
authors.affiliation: Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802 USA.
authors.forename: Hari S
authors.initials: HS
authors.lastname: Muddana
authors.affiliation: 1] Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA [2] Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA [3] Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Vincent H
authors.initials: VH
authors.lastname: Crespi
authors.affiliation: 1] Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA [2] Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802 USA.
authors.forename: Tony Jun
authors.initials: TJ
authors.lastname: Huang
mesh_terms: D000162:Acoustics; D003198:Computer Simulation; D005782:Gels / Q000737:chemistry; D009068:Movement; D011108:Polymers / Q000737:chemistry; D013499:Surface Properties; D014783:Viscosity; D014867:Water / Q000737:chemistry
chemical_list: D005782:Gels; D011108:Polymers; D014867:Water