Self‐Assembly of Octaaminoamido Derivatives of Resorcin[4]arene in Water − A “Cell‐Like” Submicron‐Scale Hydrogel Structure

We have prepared four new octaaminoamide resorcin[4]arenes having hydrocarbon chains of different lengths ( 1 , 2 : R = CH 3 ; 3 , 4 : R = C 11 H 23 ) and different terminal groups ( 1 , 3 : NH 2 ; 2 , 4 : NMe 2 ). The surface tension and self‐assembly of aqueous solutions of 2 − 4 were studied and their critical micelle concentrations (CMC) were determined. At the water/air interface, compound 2 forms a multilayer structure, whereas compound 3 forms a bilayer and compound 4 a monolayer structure. In addition, we found that compound 3 has a second CMC (CMC 2 ). A dynamic light scattering study indicated that, at a concentration of 0.1 wt% (i.e., > CMC 2 ), 3 forms nanodimensional aggregates; increasing the concentration up to 1.2 wt% results in the formation of strong transparent gels. For hydrogels having 5 wt% of 3 , SEM images demonstrated the formation of submicron‐scale “cell‐like” aggregates. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)