Modeling and simulation of electrostatically gated nanochannels

Abstract

A new method that allows for mold-free, rapid and easy-to-use prototyping of microfluidic devices comprising channels, access holes and surface modified patterns, is presented. The innovative method is based on direct photolithographic patterning of an off-stoichiometry thiol-ene (OSTE) polymer formulation, tailor-made for photolithography, which offers unprecedented spatial resolution and allows for efficient, robust and reliable, room temperature surface modification and glue-free, covalent room temperature bonding. This mold-free process does not require cleanroom equipment and therefore allows for rapid, i.e. less than one hour, design-fabricate-test cycles, using a material suited for larger scale production. The excellent photolithographic properties of this new OSTE formulation allow for unprecedented, for thiol-ene polymer systems, resolution patterning in hundreds of micrometers thick layers, 200 µm thick in this work. Moreover, we demonstrated robust (covalent) and spatially-controlled modification of the microchannel surfaces with a contact angle of 76 degrees to hydrophobic/hydrophilic areas with contact angles of 102 and 43 degrees, respectively.

Controlling ion transport through nanopores: modeling transistor behavior

“…We couple this method to the Nernst-Planck (NP) equation (NP+LEMC method) to compute flux just as PNP does. PNP is a continuum theory that, sometimes combined with the Navier-Stokes equation to describe water flux, is commonly used to study nanopores [61,62,63,64,10,65,12,66,67,68,69,22,23,70,71,72,73,9,25,27,74,75,76,77]. PNP studies that consider transistor models similar to ours will be discussed in the Discussions in relation to our results [9,25,27,76,62,67,68,23].…”

Fabrication of Centimeter Long, Ultra-Low Aspect Ratio Nanochannel Networks in Borosilicate Glass Substrates

“…This leads to dominance of surface-fiuid interactions where transport is governed by surface charge and surface energy [1^]. The surface-fluid interactions enable a broad range of applications including water desalination [5,6], molecular gating [7,8], energy transfer [9, 10], and deoxyribonucleic acid (DNA) elongation [11,12] and sieving [13] among other applications [14].…”

DNA motion induced by electrokinetic flow near an Au coated nanopore surface as voltage controlled gate

“…To better understand our experimental observations, here we use a theoretical model that consists of coupled three partial differential equations: the Poisson equation, the Nernst–Planck equation, and the Navier-Stokes equation to describe the ion transport near nanopores [15, 25–27, 30, 55, 68, 69]. The Poisson equation estimates the distribution of the electric potential in the vicinity of the nanopore and the Nernst–Planck equation describes the electric field-driven ion transports through the nanopore.…”