Kinetic Process of an Alkaline Earth Metal Ion Transmembrane through ZIF-8

J Phys Chem Lett. 2021 Jun 17;12(23):5587-5592. doi: 10.1021/acs.jpclett.1c01469. Epub 2021 Jun 10.

Abstract

The confinement effect of biological ion channels regulates the transport of molecules and ions due to angstrom-sized pores. The structure of the potassium channel has a selection region (3-4 Å), a cavity (10 Å), and a gated region, while ZIF-8 has intrinsic pores with a 3.4 Å aperture and an 11.6 Å cavity similar to those of the potassium channel. Inspired by this, we constructed the glass/ZIF-8 hybrid membrane through an electrochemical growth process to explore the kinetics of the ion transmembrane by I-V curves and electrochemical impedance spectroscopy. These complementary approaches yield highly correlated results that show that ion transportation of the ZIF-8 membrane follows Arrhenius behavior. The rates of ions are controlled by the transmembrane activation energy, in which the ionic charge and radius play an important role.

MeSH terms

  • Imidazoles / chemistry
  • Imidazoles / pharmacokinetics*
  • Ion Channels / chemistry
  • Ion Channels / pharmacokinetics
  • Ion Transport / physiology
  • Kinetics
  • Metal-Organic Frameworks / chemistry
  • Metal-Organic Frameworks / pharmacokinetics*
  • Metals, Alkaline Earth / chemistry
  • Metals, Alkaline Earth / pharmacokinetics*
  • Nanotechnology / methods*
  • Potassium Channels / chemistry
  • Potassium Channels / pharmacokinetics*

Substances

  • Imidazoles
  • Ion Channels
  • Metal-Organic Frameworks
  • Metals, Alkaline Earth
  • Potassium Channels
  • ZIF-8 metal-organic framework