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Title: Biomimetic potassium-selective nanopores
Reproducing the exquisite ion selectivity displayed by biological ion channels in artificial nanopore systems has proven to be one of the most challenging tasks undertaken by the nanopore community, yet a successful achievement of this goal offers immense technological potential. Here, we show a strategy to design solid-state nanopores that selectively transport potassium ions and show negligible conductance for sodium ions. The nanopores contain walls decorated with 4′-aminobenzo-18-crown-6 ether and single-stranded DNA (ssDNA) molecules located at one pore entrance. The ionic selectivity stems from facilitated transport of potassium ions in the pore region containing crown ether, while the highly charged ssDNA plays the role of a cation filter. Achieving potassium selectivity in solid-state nanopores opens new avenues toward advanced separation processes, more efficient biosensing technologies, and novel biomimetic nanopore systems.  more » « less
Award ID(s):
1803002
PAR ID:
10094749
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
5
Issue:
2
ISSN:
2375-2548
Page Range / eLocation ID:
eaav2568
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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