Modeling thermophoretic effects in solid-state nanopores

Maxim Belkin, Shu Han Chao, Gino Giannetti, Aleksei Aksimentiev

Research output: Contribution to journalArticlepeer-review

Abstract

Local modulation of temperature has emerged as a new mechanism for regulation of molecular transport through nanopores. Predicting the effect of such modulations on nanopore transport requires simulation protocols capable of reproducing non-uniform temperature gradients observed in experiment. Conventional molecular dynamics (MD) method typically employs a single thermostat for maintaining a uniform distribution of temperature in the entire simulation domain, and, therefore, can not model local temperature variations. In this article, we describe a set of simulation protocols that enable modeling of nanopore systems featuring non-uniform distributions of temperature. First, we describe a method to impose a temperature gradient in all-atom MD simulations based on a boundary-driven non-equilibrium MD protocol. Then, we use this method to study the effect of temperature gradient on the distribution of ions in bulk solution (the thermophoretic effect). We show that DNA nucleotides exhibit differential response to the same temperature gradient. Next, we describe a method to directly compute the effective force of a thermal gradient on a prototypical biomolecule—a fragment of double-stranded DNA. Following that, we demonstrate an all-atom MD protocol for modeling thermophoretic effects in solid-state nanopores. We show that local heating of a nanopore volume can be used to regulate the nanopore ionic current. Finally, we show how continuum calculations can be coupled to a coarse-grained model of DNA to study the effect of local temperature modulation on electrophoretic motion of DNA through plasmonic nanopores. The computational methods described in this article are expected to find applications in rational design of temperature-responsive nanopore systems.

Original languageEnglish (US)
Pages (from-to)826-838
Number of pages13
JournalJournal of Computational Electronics
Volume13
Issue number4
DOIs
StatePublished - Dec 1 2014

Keywords

  • Boundary-driven MD
  • Molecular dynamics
  • Nanofluidics
  • Non-equilibrium MD
  • Plasmonic heating
  • Soret coefficient
  • Thermodiffusion
  • Thermophoresis

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Modeling and Simulation
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Modeling thermophoretic effects in solid-state nanopores'. Together they form a unique fingerprint.

Cite this