title: Mass production of shaped particles through vortex ring freezing.
abstract: A vortex ring is a torus-shaped fluidic vortex. During its formation, the fluid experiences a rich variety of intriguing geometrical intermediates from spherical to toroidal. Here we show that these constantly changing intermediates can be 'frozen' at controlled time points into particles with various unusual and unprecedented shapes. These novel vortex ring-derived particles, are mass-produced by employing a simple and inexpensive electrospraying technique, with their sizes well controlled from hundreds of microns to millimetres. Guided further by theoretical analyses and a laminar multiphase fluid flow simulation, we show that this freezing approach is applicable to a broad range of materials from organic polysaccharides to inorganic nanoparticles. We demonstrate the unique advantages of these vortex ring-derived particles in several applications including cell encapsulation, three-dimensional cell culture, and cell-free protein production. Moreover, compartmentalization and ordered-structures composed of these novel particles are all achieved, creating opportunities to engineer more sophisticated hierarchical materials.
authors.affiliation: Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Duo
authors.initials: D
authors.lastname: An
authors.affiliation: Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Warning
authors.affiliation: Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Kenneth G
authors.initials: KG
authors.lastname: Yancey
authors.affiliation: School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Chun-Ti
authors.initials: CT
authors.lastname: Chang
authors.affiliation: School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Vanessa R
authors.initials: VR
authors.lastname: Kern
authors.affiliation: Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Ashim K
authors.initials: AK
authors.lastname: Datta
authors.affiliation: School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Paul H
authors.identifier: 0000-0002-0507-9438
authors.initials: PH
authors.lastname: Steen
authors.affiliation: Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.|Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA.|Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Luo
authors.affiliation: Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Minglin
authors.initials: M
authors.lastname: Ma