Amino Acid-Functionalized Calix[4]Resorcinarene Solubilization by Mono- and Dicationic Surfactants

Poorly water-soluble calix[4]resorcinarenes modified with amino acid (Ala, Val) at the upper rim formed a water-soluble mixed system with micelles of monocationic surfactants cetyltrimethylammonium bromide, cetyldimethyl(2-hydroxyethyl)ammonium bromide, and dicationic (gemini) surfactants, alkanediyl-α,ω-bis(dimethyltetradecylammonium bromides (14-s-14, where s = 2, 4, or 6). UV–Vis and DLS methods demonstrated that the micellar systems of surfactant/functionalized calix[4]resorcinarene underwent structural changes within a relatively narrow concentration range followed by changes in solubilization capacity and polydispersity. Gemini surfactants and monocationic/gemini mixed surfactant systems were provided selectivity in their interaction with calix[4]resorcinarene depending on the bulkiness of the substituent at the upper rim of calix[4]resorcinarene, gemini surfactant spacer length, and mixed micelles. These systems represent a direction to create biocompatible water-soluble functionalized calix[4]resorcinarene composition and may open perspectives in designing organized systems with controllable properties.