Biomimetic Nanofluidic Diode Composed of Dual Amphoteric Channels Maintains Rectification Direction over a Wide pH Range

Angew Chem Int Ed Engl. 2016 Oct 10;55(42):13056-13060. doi: 10.1002/anie.201606469.

Abstract

pH-gated ion channels in cell membranes play important roles in the cell's physiological activities. Many artificial nanochannels have been fabricated to mimic the natural phenomenon of pH-gated ion transport. However, these nanochannels show pH sensitivity only within certain pH ranges. Wide-range pH sensitivity has not yet been achieved. Herein, for the first time, we provide a versatile strategy to increase the pH-sensitive range by using dual amphoteric nanochannels. In particular, amphoteric polymeric nanochannels with carboxyl groups derived from a block copolymer (BCP) precursor and nanochannels with hydroxyl groups made from anodic alumina oxide (AAO) were used. Due to a synergistic effect, the hybrid nanochannels exhibit nanofluidic diode properties with single rectification direction over a wide pH range. The novel strategy presented here is a scalable, low-cost, and robust alternative for the construction of large-area membranes for nanofluidic applications, such as the separation of biomolecules.

Keywords: amphoteric nanochannels; block copolymers; ion transport; nanofluidic diodes; ph-gating.

Publication types

  • Research Support, Non-U.S. Gov't