Recognition uranyl

Sonnichsen SH, Nielsen PE. Enhanced uranyl photocleavage across the minor grove of all (A/T)(4) sequences indicates a similar narrow minor groove conformation. / Mol Recognit 1996 9 219-27. 

Kaneto, K. Bidan, G. Electrochemical recognition and immobilization of uranyl ions by polypyrrole film doped with calix[6]arene. Thin Solid Films. 1998, 331, 272-278... 

Obviously, high binding affinity is expected via ditopic recognition when the salt is bound to the receptor as a contact ion pair. For this purpose, besides having crown ether moieties, aromatic pendant arms can also be tagged to the receptor to achieve ditopic recognition of ion pairs or salt. Consequently, in this case, the recognition of cations involves cation- n interactions due to the aromatic pendant arms. For example, uranyl receptors, 15 and 16, endowed with aromatic pendant arms, are used as ditopic receptors of contact ion pairs/salts such as alkali metal halides and quaternary ammonium haUdes. ... 

The one-step immobilization of sulfonated calixarenes as doping anions during the anodic electropolymerization of pyrrole has also been proposed to produce cation-responsive electroactive films [308, 309]. In this way, calix[4]arene-p-tetrasulfonate and calix[6]arene-p-hexasulfonate were irreversibly incorporated into the structure. The recognition abilities of these molecules were retained after the entrapment step, as shown by the redox changes observed in the presence of trimethyl(ferrocenylmet-hyl)ammonium [308] and uranyl [309] as guest cations. 

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