Biological potassium ion channels allow selective permeation of larger K+ (ionic radius of 1.3 Å) over smaller Na+ (1.0 Å) with selectivity ratio over 1,000-fold. For decades, scientists have long sought to mimic these marvels in artificial systems, but have fallen far short of matching the exquisite ion discrimination of natural protein channels. Typically, the K+/Na+ selectivity ratio of existing artificial potassium channels is less than 40-fold. Read More