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Calixarene-Mediated Liquid-Membrane Transport of Choline Conjugates.

ABSTRACT: A series of supramolecular calixarenes efficiently transport distinct molecular species through a liquid membrane when attached to a receptor-complementary choline handle. Calix-[6]arene hexacarboxylic acid was highly effective at transporting different target molecules against a pH gradient. Both carboxylic- and phosphonic-acid-functionalized calix[4]arenes effect transport without requiring a pH or ion gradient. NMR binding studies, two-phase solvent extraction, and three-phase transport experiments reveal the necessary and subtle parameters to effect the transport of molecules attached to a choline "handle". On the other hand, rescorin[4]arene cavitands, which have similar guest recognition profiles, did not transport guest molecules. These developments reveal new approaches towards attempting synthetic-receptor-mediated selective small-molecule transport in vesicular and cellular systems.

SUBMITTER: Adhikari BB

PROVIDER: S-EPMC4493905 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Calixarene-Mediated Liquid-Membrane Transport of Choline Conjugates.

Adhikari Birendra Babu BB Fujii Ayu A Schramm Michael P MP

European journal of organic chemistry 20140501 14

A series of supramolecular calixarenes efficiently transport distinct molecular species through a liquid membrane when attached to a receptor-complementary choline handle. Calix-[6]arene hexacarboxylic acid was highly effective at transporting different target molecules against a pH gradient. Both carboxylic- and phosphonic-acid-functionalized calix[4]arenes effect transport without requiring a pH or ion gradient. NMR binding studies, two-phase solvent extraction, and three-phase transport exper ...[more]

PMID: 26161034

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