Fabrication of Magnetically Actuated Polymeric Nanorod Arrays to Mimic Biological Cilia

ORAL

Abstract

We report on successful fabrication of free-standing polymer nanorod arrays capable of actuation via externally applied magnetic fields. Our primary motivation is to mimic the ability of epithelial lung cilia to promote microscale fluid transport. Additionally, nanoscale actuator arrays of this nature have a wide variety of possible applications including microfluidics, sensing, and photonics. To fabricate these structures we utilize porous polycarbonate track-etched membranes as templates for a dispersion of a magnetic nanoparticle ferrofluid in polydimethylsiloxane (PDMS). Crosslinking of the polymer followed by subsequent dissolution of the membrane releases the rod array. With this method we have successfully fabricated rods with diameters down to 200 nanometers and lengths of 10-25 microns. Rods of various sizes have been successfully actuated with permanent magnets as well as an integrated magnetic force microscope that was developed in-house. We have demonstrated that actuation induces local fluid flow and are currently developing increased control over the array's actuation pattern to more closely resemble that of biological cilia.

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Authors

  • A.R. Shields

    University of North Carolina at Chapel Hill Department of Physics

  • B.A. Evans

    University of North Carolina at Chapel Hill - Physics Department

  • J. Deng

    US Naval Observatory, University of Virginia, Thomas Jefferson National Accelerator Facility, College of William and Mary, US Army Research Office, Brimrose Corporation of America, Hampton University, Department of Physics, University of Rajshahi, Rajshahi, Bangladesh, Department of Physics, Old Dominion University, Norfolk, VA 23529, University of North Carolina at Chapel Hill, Department of Physics, Old Dominion University, Norfolk, Virginia, Department of Physics, Korea University, Seoul, Korea, Department of Physics, University of Virginia, Charlottesville, VA, Department of Physics, Old Dominion University, Norfolk, VA, North Carolina State University and WebAssign, Raleigh, NC, North Carolina State University, Raleigh, NC, Broughton High School, Raleigh, NC, University of Wisconsin at Whitewater, Whitewater, WI, University of North Carolina-Chapel Hill Department of Physics, University of West Virginia - Chemistry Dept., ORNL, Old Dominion University, University of West Virginia Department of Chemistry, Clemson University, South Carolina Governor’s School for Science and Mathematics, College of Charleston, Rice University, Korea Research Institute of Standards and Science, Ohio State University, Wright State University, Yale U, JINR, Dubna, Univ. Fed. do Rio de Janeiro, Vanderbilt Univ./JIHIR(ORNL)/Tsinghua Univ., NSCL(MSU), LLNL, LBNL, Vanderbilt Univ./LBNL/JIHIR(ORNL), Vanderbilt Univ., Jagellonian University, University of Bonn, North Carolina A{\&T} State University, North Carolina Central University, Duke University and TUNL

  • R. Superfine

    University of North Carolina at Chapel Hill - Physics Department, University of North Carolina at Chapel Hill Department of Physics