Studies on CNTs that sieve water molecules from seawater have been summarized in a number of excellent review articles.19-24 Moreover, Hilder and Chung25 have designed a NT that can mimic the antibiotic gramicidin but with potassium conductance six times larger. This suggests that a NT-based drug, more potent in destroying microorganisms than the naturally occurring one, could be engineered. NTs have also been shown to embed into a cell membrane and conduct ions much faster than biological channels.26-28 As a result of their immense potential, artificial ion channels constructed from synthetic NTs is a unique field of research that has recently begun to gain momentum. For a number of years synthetic ion channels based on molecular structures other than NTs, such as cucubituril macrocycles, have been investigated. For further details on synthetic channels made from organic molecules, the reader is referred to a review by Sakai et al.