Neutral carrier ionophores, structures

Fig. 2, Structures of some neutral carrier ionophores used in the preparation of liquid and polymer membrane ISEs [From ref. (S5) with permission. Copyright (1982), Pergamon Press.]...

A second source of inspiration for studying the open-chained equivalents of crown ethers was the observation that a number of naturally occurring antibiotics enhance cation transport and bear a structural similarity to open-chained crown ethers. A number of groups have examined neutral synthetic ionophores and a variety of novel cation carriers is now available. This is discussed in Sect. 7.4, below. 

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