title: Remote Manipulation of Droplets on a Flexible Magnetically Responsive Film.
abstract: The manipulation of droplets is used in a wide range of applications, from lab-on-a-chip devices to bioinspired functional surfaces. Although a variety of droplet manipulation techniques have been proposed, active, fast and reversible manipulation of pure discrete droplets remains elusive due to the technical limitations of previous techniques. Here, we describe a novel technique that enables active, fast, precise and reversible control over the position and motion of a pure discrete droplet with only a permanent magnet by utilizing a magnetically responsive flexible film possessing actuating hierarchical pillars on the surface. This magnetically responsive surface shows reliable actuating capabilities with immediate field responses and maximum tilting angles of ~90°. Furthermore, the magnetic responsive film exhibits superhydrophobicity regardless of tilting angles of the actuating pillars. Using this magnetically responsive film, we demonstrate active and reversible manipulation of droplets with a remote magnetic force.
authors.affiliation: School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Jeong Hun
authors.initials: JH
authors.lastname: Kim
authors.affiliation: School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Seong Min
authors.initials: SM
authors.lastname: Kang
authors.affiliation: School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Byung Jun
authors.initials: BJ
authors.lastname: Lee
authors.affiliation: Department of Mechanical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Hangil
authors.initials: H
authors.lastname: Ko
authors.affiliation: School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Won-Gyu
authors.initials: WG
authors.lastname: Bae
authors.affiliation: School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Kahp Yang
authors.initials: KY
authors.lastname: Suh
authors.affiliation: Department of Mechanical Engineering, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: Moon Kyu
authors.initials: MK
authors.lastname: Kwak
authors.affiliation: Department of Mechanical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Hoon Eui
authors.initials: HE
authors.lastname: Jeong