title: Robust ion current oscillations under a steady electric field: An ion channel analog.
abstract: We demonstrate a nonlinear, nonequilibrium field-driven ion flux phenomenon, which unlike Teorell's nonlinear multiple field theory, requires only the application of one field: robust autonomous current-mass flux oscillations across a porous monolith coupled to a capillary with a long air bubble, which mimics a hydrophobic protein in an ion channel. The oscillations are driven by the hysteretic wetting dynamics of the meniscus when electro-osmotic flow and pressure driven backflow, due to bubble expansion, compete to approach zero mass flux within the monolith. Delayed rupture of the film around the advancing bubble cuts off the electric field and switches the monolith mass flow from the former to the latter. The meniscus then recedes and repairs the rupture to sustain an oscillation for a range of applied fields. This generic mechanism shares many analogs with current oscillations in cell membrane ion channel. At sufficiently high voltage, the system undergoes a state transition characterized by appearance of the ubiquitous 1/f power spectrum.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Yan
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Yunshan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Satyajyoti
authors.initials: S
authors.lastname: Senapati
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Jarrod
authors.initials: J
authors.lastname: Schiffbauer
authors.affiliation: Faculty of Mechanical Engineering, Micro- and Nanofluidics Laboratory, Technion-Israel Institute of Technology, Technion City 32000, Israel.
authors.forename: Gilad
authors.initials: G
authors.lastname: Yossifon
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Hsueh-Chia
authors.initials: HC
authors.lastname: Chang