Proton-assisted transport of amino acid and related polycarboxylate anions via polyammonium macrocycles

Abstract

Anion-binding and transport properties of polyamine macrocycles have been examined by liquid–liquid extraction and liquid membrane transport experiments. Some lipophilic polyamine macrocycles showed excellent transport properties, especially for polycarboxylate anions, depending on their ring structure. Their anion-extraction and transport properties were significantly different from those of the quaternary ammonium cation-surfactant trioctylmethylammonium chloride, and the mechanism involves protonation of the macrocyclic nitrogen atoms.